-
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:
Nick Andrews, whose social media persona is the Boston Card Hunter, is keeping track of items reported stolen, a number that had exceeded 1,000 by Tuesday morning.
From Los Angeles Times ● Oct. 20, 2026
Homeboy Silkscreen & Embroidery will make T-shirts featuring the Olympic torch, Homeboy and the official LA28 logo, based on a design by Fabian Debora, who leads the nonprofit’s Art Academy.
From Los Angeles Times ● Oct. 20, 2026
“Our goal from day one has been to ensure the economic benefits of the Games reach our local neighborhoods,” Reynold Hoover, LA28’s CEO, said in a statement.
From Los Angeles Times ● Oct. 20, 2026
LA28 plans to announce partnerships with a number of other local entities that will make a wide variety of items, such as stationery, toys, hats, magnets, candles and pet accessories.
From Los Angeles Times ● Oct. 20, 2026
But none of that appears in the newspaper announcement—just the date of her death and the fact that she worked as a secretary and usher.
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
And one final reminder, as much for myself as anybody else: A beautiful party and a photographable party aren’t necessarily the same thing.
From Salon ● Oct. 20, 2026
A South African woman has been killed in a shark attack off the country's east coast, in what is the first recorded such fatality this year.
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 Philippine government was established with the intent to achieve full independence.
From "At Last She Stood" by Erin Entrada Kelly
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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
“Below 1 Å is almost impossible to reach for cryo-EM,” he says.
From Nature ● Jun. 2, 2020
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
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
The Scottish government agreed with a recommendation by Sepa which allows Scottish Water to increase abstraction levels from the Allt a' Mhuilinn burn.
From BBC ● Jun. 17, 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
Continue round into Glen Pean and up to the Bealach a’ Chaorainn.
From The Guardian ● Feb. 29, 2020
His employer says he should ride a Volkswagen van called a' combi through a checkpoint about forty minutes north of town.
From "Enrique's Journey" by Sonia Nazario
![]()
Katie Hafner: In fact, they call it kind of a- a triangle of –
From Scientific American ● Sep. 21, 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
You wouldn’t ha’ believed in them first days of April that trouble was a- brewin’ fer all of us—ever’ one was feelin’ good, and we was gettin’ along so fine.”
From "Across Five Aprils" by Irene Hunt
![]()
The ponds, which cover nearly 5,000 hectares, display constantly changing colours -a view he says he never tires of.
From BBC ● Aug. 26, 2025
It was also common to see his “ Austin 3:16” T-shirts -a cheeky play on the John 3:16 Bible verse - in schools and malls across the country.
From Washington Times ● Apr. 28, 2023
I don't think the "-e" should eliminate the existing "-o" and the "-a."
From Salon ● Sep. 26, 2022
He needs to grow up or get out -a cancer in the locker room.
From New York Times ● Jan. 9, 2017
Piggy babbled: "-a conch; ever so expensive. I bet if you wanted to buy one, you'd have to pay pounds and pounds and pounds -he had it on his garden wall, and my auntie."
From "Lord of the Flies" by William Golding
![]()
"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
“Mandalorian” got an average grade of A- from audiences, according to market research firm CinemaScore.
From The Wall Street Journal ● May 24, 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
![]()
Using a. and b. is the train speeding up or slowing down?
From Textbooks ● Mar. 30, 2016
Evaluate a. and b. for t = 2, 4, and 6 seconds.
From Textbooks ● Mar. 30, 2016
Use your answers to parts a. and d. to determine which of the three options is best.
From Textbooks ● Mar. 30, 2016
In a similar fashion to a., we can approach the origin along any straight line passing through the origin.
From Textbooks ● Mar. 30, 2016
"You may be a. little ahead of us on that one, Epiphany. I don't have either of those acronyms on my list. We’ll have to check with our advisory panel."
From "The View From Saturday" by E.L. Konigsburg
![]()
A. In many ways, the campus feels the same—the curving brick paths, the historic pre-Civil War era buildings and the genteel feel.
From The Wall Street Journal ● Oct. 16, 2026
"Patients may accumulate amyloid for years before symptoms appear," said first author Christopher A. Brown, MD, PhD, an assistant professor of Neurology.
From Science Daily ● Oct. 15, 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
One influential model was developed by Krishna Rajagopal, the William A. M. Burden Professor of Physics at MIT, and his collaborators.
From Science Daily ● Oct. 6, 2026
Dr. Samuel A. Mudd was imprisoned in Florida, but his sentence was commuted by President Johnson, partly for assistance during an outbreak of illness in the prison.
From "Chasing Lincoln's Killer" by James L. Swanson
![]()
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
She was shocked in July when she saw a much larger portion of students than she’d expected hadn’t passed the AP test, including kids who had been getting A’s and B’s in class.
From The Wall Street Journal ● Oct. 1, 2026
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
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
Louth, 20 years old, said he earned all A’s and one B in his first semester and doubted he would have worked as hard had the classes been pass/fail.
From The Wall Street Journal ● Aug. 11, 2026
But look how many friends you made, how involved you got, and with straight A’s too!
From "Americanized" by Sara Saedi
![]()
As the long, 50-some-day production schedule rolls on, the viewer can feel Eleanor’s anxiety ease, allowing pride to take full control.
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 always, soul music is playing in the background.
From "Split the Sky" by Marie Arnold
![]()
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
His accent, a resonant blend of broad a's, clipped consonants and superbly rounded r's, is the same accent he used for credit in Manhattan speakeasies 20 years ago.
From Time Magazine Archive
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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
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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
Now, the pride moves in both directions — with Sofia as reverent of her mother’s work as Eleanor was of hers — meeting in the middle to stretch into the future.
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 massive merchandising push around the 2028 Summer Olympics will also include global brands such as Nike and Ralph Lauren.
From Los Angeles Times ● Oct. 20, 2026
After her successful mission, he joined the lead vehicle as American tanks roared toward the gates.
From "At Last She Stood" by Erin Entrada Kelly
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