1

a

play
noun, often capitalized, often attributive \ˈā\

Definition of a

plural

a's

or

as

play \ˈāz\
  1. 1a :  the 1st letter of the English alphabetb :  a graphic representation of this letterc :  a speech counterpart of orthographic a

  2. 2 :  the sixth tone of a C-major scale

  3. 3 :  a graphic device for reproducing the letter a

  4. 4 :  one designated a especially as the first in order or class

  5. 5a :  a grade rating a student's work as superior in qualityb :  one graded or rated with an A

  6. 6 :  something shaped like the letter A

  7. 7 capitalized :  the one of the four ABO blood groups characterized by the presence of antigens designated by the letter A and by the presence of antibodies against the antigens present in the B blood group

Examples of a in a Sentence

  1. a word that begins with an a

  2. a word that begins with a

  3. a song in the key of A

  4. She got an A on the exam.

Before 12th Century

First Known Use of a

before 12th century

Other Alphabet Terms


2

a

play
indefinite article \ə, (ˈ)ā, Canadian ˈa\

Definition of a

  1. 1 —used as a function word before singular nouns when the referent is unspecified a man overboard and before number collectives and some numbers a dozen

  2. 2 :  the same birds of a feather swords all of a length

  3. 3a —used as a function word before a singular noun followed by a restrictive modifier a man who was here yesterdayb :  any a man who is sick can't workc —used as a function word before a mass noun to denote a particular type or instance a bronze made in ancient timesd —used as a function word before a proper noun representing an example or type the attractions of a Boston or a Clevelande —used as a function word before a proper noun to indicate limited knowledge about the referent a Mr. Smith called to inquire about the jobf —used as a function word before a proper noun to distinguish the condition of the referent from a usual, former, or hypothetical condition a triumphant Ms. Jones greeted her supporters

  4. 4 —used as a function word with nouns to form adverbial phrases of quantity, amount, or degree felt a bit tired

a vs. an

In speech and writing a is used before a consonant sound. a door a human Before a vowel sound an is usual an icicle an honor but especially in speech a is used occasionally, more often in some dialects than in others. a apple a hour a obligation Before a consonant sound represented by a vowel letter a is usual a one a union but an also occurs though less frequently now than formerly. an unique such an one Before unstressed or weakly stressed syllables with initial h both a and an are used in writing. a historic an historic In the King James Version of the Old Testament and occasionally in writing and speech an is used before h in a stressed syllable. an huntress an hundred children are an heritage of the Lord — Psalms 127:3 (King James Version)

Origin and Etymology of a

Middle English, from Old English ān one — more at one


First Known Use: before 12th century


3

a

play
preposition also (ˈ)ā\

Definition of a

  1. 1 chiefly dialectal :  on, in, at

  2. 2 :  in, to, or for each twice a week

a vs. an

In speech and writing a is used before a consonant sound. a door a human Before a vowel sound an is usual an icicle an honor but especially in speech a is used occasionally, more often in some dialects than in others. a apple a hour a obligation Before a consonant sound represented by a vowel letter a is usual a one a union but an also occurs though less frequently now than formerly. an unique such an one Before unstressed or weakly stressed syllables with initial h both a and an are used in writing. a historic an historic In the King James Version of the Old Testament and occasionally in writing and speech an is used before h in a stressed syllable. an huntress an hundred children are an heritage of the Lord — Psalms 127:3 (King James Version)

Origin and Etymology of a

Middle English, from Old English a-, an, on


First Known Use: before 12th century


4

a

play
verb \ə, (ˌ)a\

Definition of a

archaic

  1. :  have I might a had husbands afore now — John Bunyan

Origin and Etymology of a

Middle English, contraction of have


First Known Use: 14th century


5

a

play
preposition \ə\

Definition of a

  1. :  of —often attached to the preceding word kinda lotta

Origin and Etymology of a

Middle English, by contraction


First Known Use: 15th century


6

a

abbreviation

Definition of a

  1. 1 absent

  2. 2 acceleration

  3. 3 acre

  4. 4 adult

  5. 5 alto

  6. 6 anode

  7. 7 answer

  8. 8 ante

  9. 9 anterior

  10. 10 are

  11. 11 area

  12. 12 atto-

  13. 13 author


1

A

abbreviation

Definition of A

  1. 1 ace

  2. 2 adenine

  3. 3 ampere


2

A

symbol

Definition of A

  1. argon


1

a-

prefix \ə\

Definition of a-

  1. 1 :  on :  in :  at abed

  2. 2 :  in (such) a state or condition afire

  3. 3 :  in (such) a manner aloud

  4. 4 :  in the act or process of gone a-hunting atingle

Origin and Etymology of a-

Middle English, from Old English


2

a-

prefix \(ˈ)ā also (ˈ)a or (ˈ)ä\
variants: or

an-

\(ˈ)an\

Definition of a-

  1. :  not :  without asexuala- before consonants other than h and sometimes even before h, an- before vowels and usually before h achromatic ahistorical anastigmatic anhydrous

Origin and Etymology of a-

Latin & Greek; Latin, from Greek — more at un-


-a-

combining form

Definition of -a-

  1. :  replacing carbon especially in a ring aza-

Origin and Etymology of -a-

perhaps from -a- in ring compounds such as thiazole (in which -a- is the initial of azole)


-a

noun suffix \ə\

Definition of -a

  1. :  oxide silica

Origin and Etymology of -a

New Latin, from -a (as in magnesia)


3

Å

abbreviation

Definition of Å

  1. angstrom unit


A Defined for English Language Learners

1

a

play
noun, often capitalized, often attributive \ˈā\

Definition of a for English Language Learners

  • : the first letter of the English alphabet

  • : a musical note or key referred to by the letter A : the sixth tone of a C-major scale

  • : a grade that is given to a student for doing excellent work

2

a

play
indefinite article \ə, (ˈ)ā, Canadian ˈa\

Definition of a for English Language Learners

  • —used before singular nouns when the person or thing is being mentioned for the first time

  • —used like one before number words like hundred, thousand, etc.

  • —used like one before number words like third, fortieth, etc.


A Defined for Kids

1

a

play
noun , often cap \ˈā\

Definition of a for Students

plural

a's

or

as

\ˈāz\
  1. 1 :  the first letter of the English alphabet

  2. 2 :  a grade that shows a student's work is excellent

  3. 3 :  a musical note referred to by the letter A


2

a

play
indefinite article \ə, ˈā\

Definition of a for Students

  1. 1 :  someone or something being mentioned for the first time There's a dog in the yard.

  2. 2 :  the same two of a kind

  3. 3 :  1any 1 It's hard for a person to understand.

  4. 4 :  for or from each an apple a day The new theater charges ten dollars a person.

  5. 5 :  2one 3 a dozen doughnuts a week This is a third the size of that. Hint: A is used before words that do not begin with a vowel sound.


a-

prefix \ə\

Definition of a- for Students

  1. 1 :  on :  in :  at abed

  2. 2 :  in (such) a state, condition, or manner afire aloud

  3. 3 :  in the act or process of gone a-hunting


Medical Dictionary

a

abbreviation

Medical Definition of a

  1. 1about

  2. 2absent

  3. 3absolute

  4. 4absorbency; absorbent

  5. 5accommodation

  6. 6acetum

  7. 7acid; acidity

  8. 8actin

  9. 9active; activity

  10. 10allergist; allergy

  11. 11alpha

  12. 12anode

  13. 13answer

  14. 14ante

  15. 15anterior

  16. 16aqua

  17. 17area

  18. 18artery

  19. 19asymmetric; asymmetry


noun \ˈā\

Medical Definition of A

  1. :  the one of the four ABO blood groups characterized by the presence of antigens designated by the letter A and by the presence of antibodies against the antigens present in the B blood group


A

abbreviation

Medical Definition of A

  1. 1adenine

  2. 2ampere



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