- 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 A to Z ⇒ from start to finish, thoroughly and in detail
WordReference Random House Learner's Dictionary of American English © 2019
A, a /eɪ/USA pronunciation
n.[countable], pl. A's or As, a's or as.
a1 /ə; when stressed eɪ/USA pronunciation indefinite article. [usually before count nouns]
A, Symbol.
a-1 ,[prefix.]a- is used before some nouns to make them into adverbs showing "place where'':a- + shore → ashore = on (or into) the shore.
a is also used before some verbs to make them into words showing a state or process:a- + sleep → asleep (= sleeping);a- + blaze → ablaze (= blazing).
a-1 ,[prefix.] a- is used before some adjectives to mean "not'': a- + moral → amoral (= without morals);
a- + tonal → atonal (= without tone).
A., an abbreviation of:
a., an abbreviation of:
WordReference Random House Unabridged Dictionary of American English © 2019- Linguisticsthe first letter of the English alphabet.
- Educationa school grade or mark indicating excellence:received an A in English.
- Idioms from A to Z, completely;
thoroughly:He knew the rules of the game from A to Z.
a1 /ə; when stressed eɪ/USA pronunciation indefinite article. [usually before count nouns]
- one:a friend of mine; a month ago.
- (used to refer to the class of things the noun belongs to): A dog has four legs.
- (used to refer to a rate or measurement with the noun) per;
each: My dentist charges $50 a filling. - (used before words like little, lot, few):a little time; a few stars.
- (used before noncount nouns to indicate a single portion, container, unit, type, or instance of that noun): I'll have a coffee (= a cup of coffee) with sugar.
- (used before a proper name):
- a certain;
a particular: A Mr. Johnson called and wants you to call back. - a work of art by:The investor paid $5 million for a Van Gogh.
- a certain;
A, Symbol.
- Music and Dance
- in music, the sixth tone of the C major scale.
- Physiologya major blood group.
a-1 ,[prefix.]
a-1 ,
a- + tonal → atonal (= without tone).
A., an abbreviation of:
- America.
- American.
a., an abbreviation of:
- acre.
- active.
- Grammaradjective.
- Music and Dancealto.
- Electricityampere.
- answer.
A, a
(ā),USA pronunciation n., pl. A's or As, a's or as.
a1 (ə; when stressed ā),USA pronunciation indefinite article.
a2 (ə; when stressed ā),USA pronunciation prep.
a3 (ə),USA pronunciation prep.
a4 (ə),USA pronunciation auxiliary verb.
a5 (ə, a, ä),USA pronunciation pron.
a' (ä, ô),USA pronunciation adj.
A ,Electricityampere;
amperes.
Physics, Educationangstrom.
Educationanswer.
British Terms, Music and Dancearterial (used with a road number to designate a major highway):Take the A525 to Ruthin.
A , Symbol.
a ,[Meas.]
a , Symbol, Logic.
Å , Symbol, Physics.
A- ,atomic (used in combination):A-bomb; A-plant.
a-1 ,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-2 ,a reduced form of the Old English preposition of: akin;
afresh;
anew.
a-3 ,an old point-action prefix, not referring to an act as a whole, but only to the beginning or end:She arose(rose up). They abided by their beliefs (remained faithful to the end).
a-4 ,var. of ab- before p and v: aperient;
avert.
a-5 ,var. of ad-, used: (1) before sc, sp, st (ascend) and (2) in words of French derivation (often with the sense of increase, addition):amass.
a-6 ,var. of an- 1 before a consonant, meaning "not,'' "without'':amoral;atonal;achromatic.
-a1 ,a plural ending of nouns borrowed from Greek and Latin:phenomena; data;errata;genera.
-a2 ,a feminine singular ending of nouns borrowed from Latin and Greek, also used in Neo-Latin coinages to Latinize bases of any origin, and as a Latin substitute for the feminine ending -ē of Greek words:anabaena;cinchona;pachysandra.
-a3 ,an ending of personal names forming feminines from masculines:Georgia; Roberta.
-a4 ,a suffix designating the oxide of the chemical element denoted by the stem:alumina;ceria;thoria.
A. ,Absolute.
Academy.
Weights and Measuresacre;
acres.
America.
American.
Weights and Measuresangstrom.
year.
answer.
before.
April.
MilitaryArtillery.
a. ,about.
acre;
acres.
active.
Grammaradjective.
Music and Dancealto.
Electricityampere;
amperes.
year.
anonymous.
answer.
before.
Weights and Measuresare;
ares.
Sport[Baseball.]assist;
assists.
- Linguisticsthe first letter of the English alphabet, a vowel.
- Linguisticsany 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.
- Printinga device, as a printer's type, for reproducing the letter A or a.
- from A to Z, from beginning to end;
thoroughly;
completely:He knows the Bible from A to Z. - not know from A to B, to know nothing;
be ignorant.
a1 (ə; when stressed ā),USA pronunciation indefinite 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(compare hundreds of men);
a dozen times (compare dozens 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.
- origin, originally preconsonantal phonetic variant of an1 Middle English
- In both spoken and written English the choice of a1 or an1 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 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.
a2 (ə; when stressed ā),USA pronunciation prep.
- Pronounseach;
every;
per:ten cents a sheet; three times a day.
- confused with a1 origin, originally Middle English a, preconsonantal variant of on (see a-1)
a3 (ə),USA pronunciation prep.
- [Pron. Spelling.]a reduced, unstressed form of of (often written as part of a single, unhyphenated word):cloth a gold; kinda;sorta.
- unstressed preconsonantal variant of of1 Middle English
a4 (ə),USA pronunciation auxiliary verb.
- [Pron. Spelling.]a reduced, unstressed form of auxiliary have following some modals, as might, should, could, would, and must (usually written as part of a single, unhyphenated word):We shoulda gone.Cf. of2.
- phonetic variant of have Middle English
a5 (ə, a, ä),USA pronunciation pron.
- [Brit. Dial.]
- British Termshe.
- British Termsshe.
- British Termsit.
- British Termsthey.
- British TermsI.
- Middle English a, ha
a' (ä, ô),USA pronunciation adj.
- Scottish Termsall:for a' that.
A ,
amperes.
A , Symbol.
- the first in order or in a series.
- (sometimes l.c.) (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.
- (sometimes l.c.) (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.
- Physiologya 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. Cf. ABO system.
- (sometimes l.c.) the medieval Roman numeral for 50 or 500. Cf. Roman numerals.
- Chemistry(formerly) argon.
- [Chem., Physics.]See mass number.
- Biochemistry
- adenine.
- alanine.
- Drugs, Philosophy[Logic.]See universal affirmative.
- British Terms, Show Businessa designation for a motion picture recommended as suitable for adults. Cf. AA (def. 5), U (def. 5), X (def. 9).
- Clothinga proportional shoe width size, narrower than B and wider than AA.
- Clothinga proportional brassiere cup size, smaller than B and larger than AA.
- Businessa quality rating for a corporate or municipal bond, lower than AA and higher than BBB.
a ,[Meas.]
- Philosophyare;
ares.
a , Symbol, Logic.
- See universal affirmative.
Å , Symbol, Physics.
- angstrom.
A- ,
a-1 ,
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).
- compare a2, nowadays Middle English, late Old English
a-2 ,
afresh;
anew.
- see a3 Middle English
a-3 ,
- *ud-s, akin to out; in some cases confused with a-4, as in abridge
- unstressed Indo-European *uss-
- Middle English; Old English a- (unstressed), ǣ-, ā-, ō- (stressed; see abb, woof1, oakum), rarely or- (see ordeal)
Gmc *uz-
a-4 ,
avert.
- Latin ab-, as in abridge
- French a-
- Latin ā-, a- (variant of ab- ab-); in some words
- Middle English
a-5 ,
- Latin a- (variant of ad- ad-), as in ascend
- Latin ad- prefix or ad preposition (see ad-), as in abut; in others
- Middle French a-
- Middle English, in some words
a-6 ,
-a1 ,
-a2 ,
-a3 ,
- Latin feminine -a (see -a2), as Claudia, feminine of Claudius
-a4 ,
- probably generalized from the -a of magnesia
A. ,
acres.
-
Latin annō, ablative of annus
-
Latin annō, ablative of annus
a. ,
acres.
amperes.
-
Latin annō, ablative of annus
-
Latin annō, ablative of annus
ares.
assists.
Collins Concise English Dictionary © HarperCollins Publishers::
a, A /eɪ/ n ( pl a's, A's, As)
a /ə; (stressed or emphatic) eɪ/ determiner (indefinite article; used before an initial consonant)
Compare an1
See the1
Compare an1
- used preceding a singular countable noun, if the noun is not previously specified or known: a dog, a terrible disappointment
- used preceding a noun or determiner of quantity: a cupful, a dozen eggs, a great many, to read a lot
- preceded by once, twice, several times, etc: 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
See the1
Collins Concise English Dictionary © HarperCollins Publishers::
A symbol for
- 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
- 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
- ampere(s)
- absolute (temperature)
- area
- (in combination) atomic: an A-bomb, an A-plant
- a person whose job is in top management, or who holds a senior administrative or professional position
- (as modifier): an A worker
See also occupation groupings
Collins Concise English Dictionary © HarperCollins Publishers::
Å symbol for
- angstrom unit
Collins Concise English Dictionary © HarperCollins Publishers::
A. abbreviation for
- acre(s) or acreage
- America(n)
- answer
Collins Concise English Dictionary © HarperCollins Publishers::
a-, (before a vowel)an- prefix
- not; without; opposite to: atonal, asocial
a- prefix
- on; in; towards: afoot, abed, aground, aback
- in the condition or state of: afloat, alive, asleep