-
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:
Responding officers found two victims who were “not cooperative” with officers and were transported to a local hospital via the Los Angeles Fire Department, Eisenman added.
From Los Angeles Times ● Oct. 18, 2026
The proportion of listed homes that eventually had a price cut peaked in 2023 and has remained relatively high since.
From BBC ● Oct. 18, 2026
Hours later, authorities issued a tactical alert about 5:30 p.m. following a report of “more than 100 young adults being unruly” near Crenshaw and Martin Luther King boulevards, Eisenman says.
From Los Angeles Times ● Oct. 18, 2026
Once on the surface, it will deploy a robotic arm and two samplers to grab some moon dust.
From BBC ● Oct. 18, 2026
Some say a mythical creature beckons children to the mountain and they are never seen again.
From "At Last She Stood" by Erin Entrada Kelly
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A space mission is set to launch on Monday that will attempt to grab a piece of Mars' moon Phobos and bring it back to Earth.
From BBC ● Oct. 18, 2026
A stock rout swept up companies from CoreWeave to Alphabet while Treasury yields tumbled.
From The Wall Street Journal ● Oct. 18, 2026
A look at the top 25 high school football teams in the Southland after Week 8:
From Los Angeles Times ● Oct. 18, 2026
Riccardo Calafiori: A loose pass in the first half which ended with a good Forest attack.
From BBC ● Oct. 18, 2026
A blind man—Stanley Stein, one of the best-known figures in Carville—steps forward and says, “Welcome, Joey. Welcome to Carville.”
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
FORS2 spectra were acquired with the 600B and 600RI grisms, covering the 3,500–8,600 Å wavelength range fully.
From Nature ● Oct. 15, 2017
Its name comes from the Scottish Gaelic word cheò, meaning mist, and is a reference to the Gaelic name of Isle of Syke - Eilean a' Cheò or Isle of Mist.
From BBC ● Feb. 5, 2024
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
Bob Dylan’s “The Times They Are a’ Changin’” is “a little bit sad and I think it’s about friends,” he wrote.
From Washington Times ● Oct. 8, 2016
‘The voice is right, and your face is no worse than it was, Sam. But I should a’ passed you in the street in that gear.
From "The Return of the King" by J.R.R. Tolkien
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And Robert Heath was sort of a- adventurous entrepreneur of a neurologist and psychiatrist.
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
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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
The eyes of some animal peer at me from the neighboring tree -a possum maybe -catching the firelight from the Careers' torches.
From "The Hunger Games" by Suzanne Collins
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"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
A recent report card from Children Now, a nonprofit advocacy group, rated California a D on children’s access to preventive care, despite the state’s A- grade for ensuring children have coverage.
From Los Angeles Times ● Feb. 26, 2024
Normally it’s sort of fun to count the A- , B-, and Z-listers shilling for mayonnaise and sneakers.
From Slate ● Feb. 12, 2024
I charged a dollar per assignment and guaranteed at least an A- or the customer was entitled to a full refund.
From "The Glass Castle" by Jeannette Walls
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For the following exercises, a. find the inverse function, and b. find the domain and range of the inverse function.
From Textbooks ● Mar. 30, 2016
Evaluate a. and b. for t = 2, 4, and 6 seconds.
From Textbooks ● Mar. 30, 2016
Determine the requested vectors and express each of them a. in component form and b. by using the standard unit vectors.
From Textbooks ● Mar. 30, 2016
You may notice that the graphs in parts a. and b. are identical.
From Textbooks ● Mar. 30, 2016
The flutter of cards, motion of hands, of eyelids, the drone of the time-voice in the firehouse ceiling “...one thirty-five. Thursday morning, November 4th,... one thirty-six... one thirty-seven a. m...”
From "Fahrenheit 451" by Ray Bradbury
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Investors are mainly in a wait-and-see mode ahead of major U.S. bank earnings and inflation data this week, says Peter A. Grant, vice president and senior metals strategist at Zaner Metals in a note.
From The Wall Street Journal ● Oct. 13, 2026
“Even with respectable ancillary income based on the film’s pedigree, the movie is going to lose a lot of money,” David A. Gross wrote in his FranchiseRe movie industry newsletter shortly after the film’s opening.
From Los Angeles Times ● Oct. 12, 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
A fact that no one has shared with Axel before, not Ms. Dale or Dr. Martin, not Emmett or even A. P. Brown’s Collection of North American Birds.
From "A Bird Will Soar" by Alison Green Myers
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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
Sixty percent of grades at Harvard College were A’s in the 2024-25 academic year, up from 24% in 2005-06.
From The Wall Street Journal ● Oct. 8, 2026
Hong Leong cuts Capital A’s target price to 0.69 ringgit from 0.76 ringgit, while maintaining a buy rating on the stock.
From The Wall Street Journal ● Aug. 28, 2026
In May, Harvard University faculty voted to approve a 20% cap on the number of A’s per undergraduate course in an effort to curb grade inflation.
From The Wall Street Journal ● Aug. 11, 2026
“He definitely has the consistency side of things down pat,” fellow A’s infielder Tommy White told reporters.
From Los Angeles Times ● Aug. 10, 2026
I’d earned A’s in every subject except Western Civ.
From "Educated" by Tara Westover
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"As soon as he struck it, I knew it was in. He's taken the club goal of the season off me," joked Brighton skipper Dunk.
From BBC ● Oct. 18, 2026
As of 2026 the world is “likely below replacement fertility,” Messrs. Fernández-Villaverde and Norrick write.
From The Wall Street Journal ● Oct. 18, 2026
As a result, hundreds of women were affected, and many were compelled to resign.
From Los Angeles Times ● Oct. 18, 2026
As the brain ages, these cells can lose some of their ability to perform these essential tasks.
From Science Daily ● Oct. 18, 2026
As SJ’s stout fingers zip across the controls, a soft blue light envelops you; there’s no roar of fuel combustion or electrical hum.
From "Legendary Frybread Drive-In" by Cynthia Leitich Smith
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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
As a foriner, ce hardest cing in English to lern is ce usage of ce's and a's.
From Time Magazine Archive
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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
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Dr. Finch rolled out the last name in Maycomb County accents: long a’s, i s, and a pause between syllables.
From "Go Set a Watchman: A Novel" by Harper Lee
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The incidents “did not impact operations” and the event “ended as planned.”
From Los Angeles Times ● Oct. 18, 2026
There is a statutory review of the measures for veterans to ensure they "deliver as intended"
From BBC ● Oct. 18, 2026
The state’s population never recovered from Covid-19, and it’s still down about 201,000, as of 2025.
From The Wall Street Journal ● Oct. 18, 2026
Property portals say buyers are now having to be choosy, with many working to a tight budget as mortgage rates have risen to three-year highs.
From BBC ● Oct. 18, 2026
She was accused of witchcraft and the crime of dressing as a man.
From "At Last She Stood" by Erin Entrada Kelly
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