-
a
aindefinite articlenot any particular or certain one of a class or group.
-
A
Anounthe first letter of the English alphabet, a vowel.
-
Å
Åangstrom.
-
a'
a'adjectiveall.
-
a-
a-a reduced form of the Old English preposition on, meaning “on,” “in,” “into,” “to,” “toward,” preserved before a noun in a prepositional phrase, forming a predicate adjective or an adverbial element (afoot; abed; ashore; aside; away ), or before an adjective (afar; aloud; alow ), as a moribund prefix with a verb (acknowledge ), and in archaic and dialectal use before a present participle in -ing (set the bells aringing ); and added to a verb stem with the force of a present participle (ablaze; agape; aglow; astride; and originally,awry ).
-
-a
-aa plural ending of nouns borrowed from Greek and Latin.
-
A-
A-atomic (used in combination).
-
a.
a.abbreviationyear.
-
A.
A.abbreviationyear.
-
a–
a–A prefix meaning “without” or “not” when forming an adjective (such as amorphous, without form, or atypical, not typical), and “absence of” when forming a noun (such as arrhythmia, absence of rhythm). Before a vowel or h it becomes an– (as in anhydrous, anoxia).
a
1 Americanindefinite article
-
not any particular or certain one of a class or group.
a man; a chemical; a house.
-
a certain; a particular.
one at a time; two of a kind; A Miss Johnson called.
-
another; one typically resembling.
a Cicero in eloquence; a Jonah.
-
one (used before plural nouns that are preceded by a quantifier singular in form): a hundred men (comparehundreds of men ); a dozen times (comparedozens of times ).
-
indefinitely or nonspecifically (used with adjectives expressing number).
a great many years; a few stars.
-
one (used before a noun expressing quantity).
a yard of ribbon; a score of times.
-
any; a single.
not a one.
preposition
preposition
auxiliary verb
abbreviation
noun
-
A's,
plural
-
As,
plural
-
a's,
plural
-
as
plural
-
the first letter of the English alphabet, a vowel.
-
any spoken sound represented by the letter A or a, as in bake, hat, father, or small.
-
something having the shape of an A .
-
a written or printed representation of the letter A or a.
-
a device, as a printer's type, for reproducing the letter A or a.
idioms
-
not know from A to B, to know nothing; be ignorant.
-
from A to Z, from beginning to end; thoroughly; completely.
He knows the Bible from A to Z.
-
the first in order or in a series.
-
Sometimes a
-
(in some grading systems) a grade or mark, as in school or college, indicating the quality of a student's work as excellent or superior.
-
(in some school systems) a symbol designating the first semester of a school year.
-
-
Music.
-
the sixth tone in the scale of C major or the first tone in the relative minor scale, A minor.
-
a string, key, or pipe tuned to this tone.
-
a written or printed note representing this tone.
-
(in the fixed system of solmization) the sixth tone of the scale of C major, called la.
-
the tonality having A as the tonic note.
-
-
Physiology. a major blood group, usually enabling a person whose blood is of this type to donate blood to persons of group A or AB and to receive blood from persons of O or A.
-
Sometimes a the medieval Roman numeral for 50 or 500.
-
Chemistry. (formerly) argon.
-
Chemistry, Physics. mass number.
-
Biochemistry.
-
Logic. Also a universal affirmative.
-
British. a designation for a motion picture recommended as suitable for adults.
-
a proportional shoe width size, narrower than B and wider than AA.
-
a proportional brassiere cup size, smaller than B and larger than AA.
-
a quality rating for a corporate or municipal bond, lower than AA and higher than BBB.
adjective
abbreviation
abbreviation
abbreviation
-
about.
-
acre; acres.
-
active.
-
adjective.
-
alto.
-
ampere; amperes.
-
anonymous.
-
answer.
-
are; ares.
-
Baseball. assist; assists.
abbreviation
abbreviation
abbreviation
-
Absolute.
-
Academy.
-
acre; acres.
-
America.
-
American.
-
angstrom.
-
answer.
-
April.
-
Artillery.
symbol
-
music
-
a note having a frequency of 440 hertz ( A above middle C ) or this value multiplied or divided by any power of 2; the sixth note of the scale of C major
-
a key, string, or pipe producing this note
-
the major or minor key having this note as its tonic
-
-
a human blood type of the ABO group, containing the A antigen
-
(in Britain) a major arterial road
the A3 runs from London to Portsmouth
-
-
a film certified for viewing by anyone, but which contains material that some parents may not wish their children to see
-
( as modifier )
an A film
-
-
mass number
-
the number 10 in hexadecimal notation
-
cards ace
-
chem argon (now superseded by Ar )
-
ampere(s)
-
Also: at. ampere-turn
-
absolute (temperature)
-
(in circuit diagrams) ammeter
-
area
-
(in combination) atomic
an A-bomb
an A-plant
-
chem affinity
-
biochem adenine
-
logic a universal affirmative categorical proposition, such as all men are mortal: often symbolized as SaP Compare E I 2 O 1
-
-
a person whose job is in top management, or who holds a senior administrative or professional position
-
( as modifier ) See also occupation groupings
an A worker
-
abbreviation
determiner
-
used preceding a singular countable noun, if the noun is not previously specified or known
a dog
a terrible disappointment
-
used preceding a proper noun to indicate that a person or thing has some of the qualities of the one named
a Romeo
a Shylock
-
used preceding a noun or determiner of quantity
a cupful
a dozen eggs
a great many
to read a lot
-
used preceding a noun indicating a concrete or abstract thing capable of being divided
half a loaf
a quarter of a minute
-
each or every; per
once a day
fifty pence a pound
-
a certain; one
to change policy at a stroke
a Mr Jones called
-
(preceded by not) any at all
not a hope
symbol
-
acceleration
-
are(s) (metric measure of land)
-
atto-
-
chess See algebraic notation
noun
-
the first letter and first vowel of the modern English alphabet
-
any of several speech sounds represented by this letter, in English as in take, bag, calm, shortage, or cobra
-
Also called: alpha. the first in a series, esp the highest grade or mark, as in an examination
-
from start to finish, thoroughly and in detail
abbreviation
-
acre(s) or acreage
-
America(n)
-
answer
prefix
-
on; in; towards
afoot
abed
aground
aback
-
literary (used before a present participle) in the act or process of
come a-running
go a-hunting
-
in the condition or state of
afloat
alive
asleep
symbol
prefix
verb
preposition
determiner
Grammar
In both spoken and written English the choice of a1 or an 1 is determined by the initial sound of the word that follows. Before a consonant sound, a is used; before a vowel sound, an : a book, a rose; an apple, an opera. Problems arise occasionally when the following word begins with a vowel letter but actually starts with a consonant sound, or vice versa. Some words beginning with the vowel letter u and all words beginning with the vowel letters eu are pronounced with a beginning consonant sound, as if the first letter were y : a union; a European. Some other spellings that begin with a vowel letter may also stand for an initial consonant sound: a ewe; a ewer. The words one and once and all compounds of which they are the first element begin with a w sound: a one-room apartment; a once-famous actor. The names of the consonant letters f, h, l, m, n, r, s, and x are pronounced with a beginning vowel sound. When these letters are used as words or to form words, they are preceded by an : to rent an L-shaped studio; to fly an SST. The names of the vowel letter u and the semivowel letters w and y are pronounced with a beginning consonant sound. When used as words, they are preceded by a : a U-turn; The plumber installed a Y in the line. In some words beginning with the letter h, the h is not pronounced; the words actually begin with a vowel sound: an hour; an honor. When the h is strongly pronounced, as in a stressed syllable at the beginning of a word, it is preceded by a : a history of the Sioux; a hero sandwich. (In former times an was used before strongly pronounced h in a stressed first syllable: an hundred. ) Such adjectives as historic, historical, heroic, and habitual, which begin with an unstressed syllable and often with a silent or weakly pronounced h, are commonly preceded by an, especially in British English. But the use of a rather than an is widespread in both speech and writing: a historical novel; a habitual criminal. Hotel and unique are occasionally preceded by an, but this use is increasingly old-fashioned. Although in some dialects an has yielded to a in all cases, edited writing reflects usage as described above.
Other Word Forms
Noun Inflected Forms
Etymology
Origin of a1
First recorded in 1200–50; Middle English; originally preconsonantal phonetic variant of an 1
Origin of a2
Originally Middle English a, preconsonantal variant of on ( a- 1 ); confused with a 1
Origin of a3
Middle English; unstressed preconsonantal variant of of 1
Origin of a4
First recorded in 1300–50; Middle English; a phonetic variant of have
Origin of a5
First recorded in 1200–50; Middle English a, ha
Origin of a-12
Middle English, late Old English; cf. a 2, nowadays
Origin of a-13
Middle English; see a 3
Origin of a-14
Middle English; Old English a- (unstressed), ǣ-, ā-, ō- (stressed; see abb, woof 1, oakum), rarely or- ( see ordeal), ultimately from unattested Germanic uz- from unstressed Indo-European uss-, from ud-s (these latter two also unattested), akin to out; in some cases confused with a- 4, as in abridge
Origin of a-15
Middle English < Latin ā-, a- (variant of ab- ab- ); in some words < French a- < Latin ab-, as in abridge
Origin of a-16
Middle English, in some words < Middle French a- < Latin ad- prefix or ad preposition ( ad- ), as in abut; in others < Latin a- (variant of ad- ad- ), as in ascend
Origin of -a20
From Latin feminine ending -a, as Claudia, feminine of Claudius; see -a 2
Origin of -a21
Probably generalized from the -a of magnesia
Origin of a.23
< Latin annō, ablative of annus
Origin of a.24
From the Latin word ante
Origin of A.26
< Latin annō, ablative of annus
Origin of A.27
From the Latin word ante
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
U2 — which features singer Bono, lead guitarist the Edge, bass player Adam Clayton and drummer Larry Mullen Jr. — celebrated their 50th anniversary last month with a concert.
From Los Angeles Times ● Oct. 20, 2026
U2 is coming to SoFi Stadium for the first time — and performing during a Rams game for the first time in nearly 25 years.
From Los Angeles Times ● Oct. 20, 2026
PSA said it was taking measures to prevent the stolen cards from circulating through the usual venues and marketplaces while also reimbursing card owners for at least a portion of their losses.
From Los Angeles Times ● Oct. 20, 2026
Now some of them will get a chance to manufacture and sell Olympic-branded merchandise.
From Los Angeles Times ● Oct. 20, 2026
She has a dresser with a small mirror and a cabinet with a two-plate burner, record player, and records.
From "At Last She Stood" by Erin Entrada Kelly
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A Miami real estate magnate purchased the autographed road jersey, which Jordan wore during Game 2 of the 1988 Finals.
From Los Angeles Times ● Oct. 20, 2026
A dedicated archivist of her own life via journals and film, Eleanor spent much of her time trailing her husband, Francis Ford Coppola, and children between their movie sets to document the arduous filmmaking process.
From Salon ● Oct. 20, 2026
A truck carrying around 200 mourners which had travelled from an area north of Abyei was hit as it arrived in the town of Al-Dabab in West Kordofan, the monitoring group said.
From BBC ● Oct. 20, 2026
A retiree who wants out in year two pays roughly a tenth of his savings for the privilege.
From MarketWatch ● Oct. 20, 2026
A little boy with jet-black hair and dark eyes comes up to Ford and says something in Spanish.
From "Split the Sky" by Marie Arnold
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In the new study, the research team employed state-of-the-art cryo-electron microscopy techniques to capture nine different states associated with the lipid transport and determine structures at 2.4 to 3.1 Å resolution for these states.
From Science Daily ● Dec. 5, 2023
Danish, an often staccato language spoken by only about six million people and whose alphabet includes the letters Æ, Ø and Å, is perhaps an unlikely choice for pop’s next lingua franca.
From New York Times ● Apr. 19, 2023
Note: The length unit angstrom, Å, is often used to represent atomic-scale dimensions and is equivalent to 10−10 m.
From Textbooks ● Feb. 14, 2019
At the first epoch, all deviations from the blackbody spectrum are below about 10% in the range 3,500 Å–20,000 Å, indicating that the fit is very satisfactory.
From Nature ● Oct. 15, 2017
Two or more such β-sheets lie in parallel, 6–12 Å apart.
From Nature ● Nov. 8, 2016
Some songs—such as “A Guid New Year to ane a’ A’”—were widely recognized.
From National Geographic ● Dec. 27, 2023
Whether all this adds up to some big change a’ coming to City Hall, it’s too soon to say.
From Seattle Times ● May 24, 2023
After a’ dominating Thanksgiving win over Dallas two-plus years ago, Anthony posted a clip of his brother’s leaping pick-six of quarterback Andy Dalton and urged people to vote for Sweat to make the Pro Bowl.
From Washington Times ● Jan. 5, 2023
Continue round into Glen Pean and up to the Bealach a’ Chaorainn.
From The Guardian ● Feb. 29, 2020
Well, Melias went left for a’ that—and he came by ill-luck stricken through the hauberk at the hands or some mysterious knight wha rode upon him, as Galahad foretold.
From "The Once and Future King" by T. H. White
![]()
And, uh, you know, it's just a- a very bad situation.
From Scientific American ● May 4, 2023
That giant thing of spices that looks like a-
From Salon ● Mar. 30, 2019
Average sizes are about 2.0 μm and 1.2 μm along the a- and c-axes, respectively. b, AFM height image and height profiles for the MFI nanosheets.
From Nature ● Mar. 14, 2017
The Israeli grandmaster plays the positional side of a Benko Gambit to perfection, building up great pressure on the a- and b-files while the great Benko bishop strafes the White position from g7.
From Washington Times ● May 12, 2015
The thin wooden door split with a- thunderous ciack beneath the heel of Shagga's boot.
From "A Clash of Kings" by George R.R. Martin
![]()
Usually words ending in "-o" are masculine and those ending in "-a" are feminine, but there are many common words that break those gender rules, like "la mano," the word for "hand."
From Salon ● Sep. 26, 2022
In person, you do things like a basic fitness test -a bleep test - but you don't need qualifications.
From BBC ● Apr. 12, 2022
He needs to grow up or get out -a cancer in the locker room.
From New York Times ● Jan. 9, 2017
But this much you can be sure of -a victory at that level of competition is truly a net positive for months, perhaps years, ahead.
From Washington Times ● May 25, 2016
"Well, those are not the reasons I'd have given, but . . ." He had touched her cheek, his thumb lightly tracing the line of -a cheek-bone.
From "A Game of Thrones" by George R.R. Martin
![]()
At the University of Michigan, a review by the news site MLive found that 74.1% of all undergraduate grades in 2022 were an A+, A or A-.
From The Wall Street Journal ● Aug. 11, 2026
"The All Blacks are a classy outfit, and they'll punish you if you're not on your A- game, and at times we weren't," admitted Irish skipper Dan Sheehan.
From BBC ● Jul. 18, 2026
Normally it’s sort of fun to count the A- , B-, and Z-listers shilling for mayonnaise and sneakers.
From Slate ● Feb. 12, 2024
The film currently sits with a 96% rating from critics and a 91% audience score at review aggregate site Rotten Tomatoes as well as an A- in the poll from CinemaScore.
From Los Angeles Times ● Dec. 10, 2023
"W t's the Hand's tourney that's the cause of all the trou- I ble, my lords," the Commander of the City Watch A- complained to the king's council.
From "A Game of Thrones" by George R.R. Martin
![]()
Find the derivative of the equation in a. and explain its physical meaning.
From Textbooks ● Mar. 30, 2016
In part a. we showed that RN < 1/2N 2.
From Textbooks ● Mar. 30, 2016
Using a. and b. is the train speeding up or slowing down?
From Textbooks ● Mar. 30, 2016
Use a. to find the rate at which the volume is changing at t = 1 min.
From Textbooks ● Mar. 30, 2016
“I wish I could live somewhere where there were books all around. In a real town, with a. real library. And I could read about pirates or explorers or anything.”
From "Hattie Big Sky" by Kirby Larson
![]()
"We are tremendously excited and cautiously optimistic that our results could one day translate into a simple way to improve care and outcomes for people with pre-leukemia disorders," said Peter A. Jones, Ph.D.,
From Science Daily ● Oct. 20, 2026
The film triumphed despite poor reviews and audience reception, according to analyst David A. Gross of Franchise Entertainment Research.
From Barron's ● Oct. 11, 2026
Both Peng and Zhu began working on the project in the laboratory of Garnet Chan, Bren Professor of Chemistry and director of the Rudolph A. Marcus Center for Theoretical Chemistry at Caltech.
From Science Daily ● Oct. 10, 2026
In her 2021 book “The Fishmeal Revolution,” Kristin A. Wintersteen traces how the Humboldt Current — a cold, nutrient-rich upwelling system along the Pacific coast of South America — was reimagined as a protein mine.
From Los Angeles Times ● Oct. 9, 2026
A. H. Lacson, a journalist for The Manila Times and former guerrilla scout, makes a trip to Tala Leprosarium to see things for himself.
From "At Last She Stood" by Erin Entrada Kelly
![]()
You know, that’s actually the easiest of all things, if you look, cause it’s such a–
From Slate ● Jan. 22, 2020
The montage ends with a honest rap from Issa: “I don’t want to be here, but my ex won’t take me back. So my broken a– is here, small-talking over apps.”
From Washington Post ● Jul. 28, 2017
We created a– civilian review board, gave them their own detectives.
From Time ● Jan. 17, 2016
MELBER: Now your path here– involved time as a– as a lawyer and a prosecutor.
From MSNBC ● Feb. 12, 2015
But whatever happens, you’ll 240 believe I’ve done my best, won’t you?–even if I’m not a– Promise me straight, you’ll lock up tight every night.”
From Into the Primitive by Robert Ames Bennett
Much like the myth of automatically getting straight A’s if your college roommate dies, there is folklore around military pilots who eject from jets and live to tell.
From The Wall Street Journal ● Sep. 15, 2026
Grade inflation has become so endemic that 44% of students who scored below 1000 on the SAT—roughly the bottom half—reported receiving all or mostly A’s.
From The Wall Street Journal ● Sep. 13, 2026
With A’s on his report card and the energy and determination to never stop improving, Benson is headed on a path that could take him in many different directions.
From Los Angeles Times ● Sep. 6, 2026
In Las Vegas, Kim envisions baseball fans walking through Bally’s restaurants, bars and entertainment spaces on their way to A’s games, much as fans now stream through the neighborhoods surrounding older urban ballparks.
From The Wall Street Journal ● Aug. 31, 2026
“Sabeen, do you always get A’s on homework?”
From "Towers Falling" by Jewell Parker Rhodes
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As the year came to a close, FBI agent Michelle Ball felt she had enough material to move forward.
From Salon ● Oct. 20, 2026
As a BBC user, you are going to hear much more about cuts in the coming months.
From BBC ● Oct. 20, 2026
As the first “Magnificent Seven” company to report earnings, Meta will set the tone for the other Big Tech companies that are investing heavily in AI.
From MarketWatch ● Oct. 20, 2026
As he told The Times last year, multiple chefs and restaurateurs expressed interest in purchasing Cole’s.
From Los Angeles Times ● Oct. 20, 2026
As quick as it came, the hum fell away, whisked off by the howling wind of Pain.
From "The Undead Fox of Deadwood Forest" by Aubrey Hartman
![]()
Like other Romance languages, Spanish divides most endings of nouns into masculine o’s or feminine a’s.
From Washington Times ● Dec. 12, 2021
And then, every fourth January, we’re suddenly expected to say it, to spell it, to know where to place the u’s and a’s.
From New York Times ● Jan. 19, 2017
The U.A.W. also objects to Hon a's habit of calling its employees "associates," complaining that this is intended to blur labor-management distinctions in the workers' minds.
From Time Magazine Archive
![]()
But there is no doubt who is the original source of the line, and his last name is spelled with two a's.
From Time Magazine Archive
![]()
“He spells it with one a. The two a’s seem a little fancy to his friends.”
From "East of Eden" by John Steinbeck
![]()
The group performed at Mount Temple Comprehensive School, where the four members were students when they first got together as a band in 1976.
From Los Angeles Times ● Oct. 20, 2026
Here we are, two decades on, watching her documentary further cement Sofia’s film as the modern classic it is.
From Salon ● Oct. 20, 2026
New scenes from The Jolly Boys' Outing include an extended look at the coach trip to Margate as well as the entire footage of the group's rollercoaster ride at Dreamland from the 1989 Christmas episode.
From BBC ● Oct. 20, 2026
The legendary Irish rock band will headline the halftime show for the NFL’s first Thanksgiving eve game as the Rams host the Green Bay Packers on Nov. 25.
From Los Angeles Times ● Oct. 20, 2026
Chaulmoogra oil, which is extracted from seeds of a tropical tree called Hydnocarpus wightiana, was used to treat leprosy for centuries, perhaps as early as the 1300s.
From "At Last She Stood" by Erin Entrada Kelly
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