The letter A.
An example of a is the first letter in the word "apple."
nounpl. A's, a's
- the first letter of the English alphabet: from the Greek alpha, a borrowing from the Phoenician
- any of the speech sounds that this letter represents, as, in English, the vowel (a) of hat, (ä) of father, (?) of bake, or (ô) of call
- a type or impression for a or A
- the first in a sequence or group
- an object shaped like
- of a or A
- first in a sequence or group
- shaped like
from A to Z
- one; one sort of: we planted a tree
- each; any one [a gun is dangerous]: a connotes a thing not previously noted or recognized, in contrast with the, which connotes a thing previously noted or recognized
Origin of aform of an before consonants: see an, adj.
Origin of a< OE an, on, in, on, at
- Physics acceleration
Origin of aClassical Latin ante meridiem AM: 7:00 a
- are (unit of area)
- a blood type
- Educ. a grade indicating excellence: an A in history
- the sixth tone or note in the ascending scale of C major
- a key, string, etc. producing this tone
- the scale having this tone as the keynote
- Physics absolute
- angstromalso Å
- Archaic, Chem. argon
- in, into, on, at, to: ashore, abed
- in the act or state of: asleep, a-crying, a-wishing
Origin of a-weakened form of Old English an, on, in, on
Origin of a-Old English a-, out of, up up, out: now generally used as an intensive: awake, arise
Origin of a-OE of-, af- off, of: akin
Origin of a-Gr a-, an-, not not, without: it becomes an- before a vowel: amoral, atypical
- ab-: used before m, p, or v: avert
- ad-: used before sc, sp, or st: ascribe
- a ligature used to represent a diphthong in some Latin words, equivalent to ai in Greek, usually written æ or replaced by e in modern spelling of derived English words, as in demon (daemon), ether (aether), etc. and pronounced (?, i, or e)
- an Old English ligature representing a low front unrounded vowel like that in Modern English hat
- a character in the International Phonetic Alphabet and some other transcription systems, representing this low front unrounded vowel
Origin of æClassical Latin aetatis
nounpl. a's, or A's also as or As
- The first letter of the modern English alphabet.
- Any of the speech sounds represented by the letter a.
- The first in a series.
- Something shaped like the letter A.
- A The best or highest in quality or rank: grade A milk.
- Music a. The sixth tone in the scale of C major or the first tone in the relative minor scale.b. A key or scale in which A is the tonic.c. A written or printed note representing this tone.d. A string, key, or pipe tuned to the pitch of this tone.
- A One of the four major blood groups in the ABO system. Individuals with this blood group have the A antigen on the surface of their red blood cells, and the anti-B antibody in their blood serum.
Marquee, Radio City Music Hall
Opened in 1932, Radio City Music Hall is a landmark in New York's Rockefeller Center.
- Used before nouns and noun phrases that denote a single but unspecified person or thing: a region; a person.
- Used before terms that denote number, amount, quantity, or degree: only a few of the voters; a bit more rest; a little excited.
- a. Used before a proper name to denote a type or a member of a class: the wisdom of a Socrates.b. Used before a mass noun to indicate a single type or example: a dry wine.
- The same: birds of a feather.
- Any: not a drop to drink.
Origin of aMiddle English variant of an an ; see an 1.
Usage Note: In writing, the form a is used before a word beginning with a consonant sound, regardless of its spelling ( a frog, a university, a euphemism ). The form an is used before a word beginning with a vowel sound ( an orange, an hour ). • An was once a common variant before words beginning with h in which the first syllable was unstressed; thus 18th-century authors wrote either a historical or an historical but a history, not an history. This usage made sense in that people often did not pronounce the initial h in words such as historical and heroic, but by the late 19th century educated speakers usually gave their initial h 's a huff, and the practice of writing an before such words began to die out. Nowadays it survives primarily before the word historical. One may also come across it in the phrases an hysterectomy or an hereditary trait. These usages are acceptable in formal writing.
Origin of aMiddle English from Old English an in ; see on .
Origin of aMiddle English alteration of haven to have ; see have .
- are (measurement)
- Games ace
- or Å angstrom
- Sports assist
- Latin anno (in the year)
- Latin annus (year)
- Latin ante (before)
Origin of a-Greek; see ne in Indo-European roots.
- On; in: abed.
- In the act of: aborning.
- In the direction of: astern.
- In a specified state or condition: abuzz.
Origin of a-Middle English from Old English from an on ; see on . Our Living Language Prefixing a- to verb forms ending in -ing, as in a-hunting and a-fishing, was once fairly common in vernacular US speech, particularly in the highland areas of the South and in the Southwest. Such verb forms derive from an Old English construction in which a preposition, usually on, was placed in front of a verbal noun—a verb to which -ing had been added to indicate that the action was extended or ongoing. Gradually such prepositions were shortened to a-. The -ing forms came to be regarded as present participles rather than verbal nouns, and the use of a- was extended to genuine present participles. Eventually a- disappeared from many dialects, including Standard English in the United States and Great Britain, although it is still retained today in some isolated dialect areas. Today, speakers who use the a- prefix do not use it randomly. Rather, a- is only used with -ing words that begin with a consonant, have stress on the first syllable, and function as part of a verb phrase, as in She was a-running.
(lower case, upper case A)
In English, the letter a usually denotes the near-open front unrounded vowel (IPA: /æ/), as in pad, the open back unrounded vowel (IPA: /ɑː/) as in father, or, followed by another vowel, the diphthong IPA: /eɪ/, as in ace.
a is the third-most common letter in English.
(plural a's or as or aes)
- The name of the Latin script letter A/a.
From Middle English and Old English lower case letter a and split of Middle English and Old English lower case letter æ.
- Old English lower case letter a from 7th century replacement by Latin lower case letter a of the Anglo-Saxon Futhorc letter ᚪ (a, “āc”), derived from Runic letter ᚫ (a, “Ansuz”).
- Old English lower case letter æ from 7th century replacement by Latin lower case ligature æ of the Anglo-Saxon Futhorc letter ᚫ (æ, “æsc”), also derived from Runic letter ᚫ (a, “Ansuz”).
- One; any indefinite example of; used to denote a singular item of a group. [First attested prior to 1150]
- There was a man here looking for you yesterday.
- Used in conjunction with the adjectives score, dozen, hundred, thousand, and million, as a function word.
- I've seen it happen a hundred times.
- One certain or particular; any single. [First attested between around 1150 to 1350]
- We've received an interesting letter from a Mrs. Miggins of London.
- The same; one. [16th Century]
- We are of a mind on matters of morals.
- Any, every; used before a noun which has become modified to limit its scope; also used with a negative to indicate not a single one.
- A man who dies intestate leaves his children troubles and difficulties.
- He fell all that way, and hasn't a bump on his head?
- Used before plural nouns modified by few, good many, couple, great many, etc.
- Someone or something like; similar to; Used before a proper noun to create an example out of it.
- The center of the village was becoming a Times Square.
Middle English, from Old English ān (“one, a, lone, sole”). The "n" was gradually lost before consonants in almost all dialects by the 15th century.
- (archaic) To do with position or direction; In, on, at, by, towards, onto. [First attested before 1150]
- Stand a tiptoe.
- To do with separation; In, into. [First attested before 1150]
- Torn a pieces.
- To do with time; Each, per, in, on, by. [First attested before 1150]
- I brush my teeth twice a day.
- To do with status; In. [First attested before 1150]
- (archaic) To do with process, with a passive verb; In the course of, experiencing. [First attested before 1150]
- (archaic) To do with an action, an active verb; Engaged in. [16th century]
- (archaic) To do with an action/movement; To, into. [16th century]
(third-person singular simple present -, present participle -, simple past and past participle -)
- Now often attached to preceding auxiliary verb. See -a.
- 1874 Thomas Hardy, Far from the Madding Crowd (Barnes & Noble Classics reprint [reset], 2005, chapter 5, page 117; from "Hardy's 1912 Wessex edition"):
- "And how Farmer James would cuss, and call thee a fool, wouldn't he, Joseph, when 'a seed his name looking so inside-out-like?" continued Matthew Moon, with feeling. / "Ay — 'a would," said Joseph meekly.
- (he): From Middle English a, ha (“he”), unstressed variant of he, from Old English hē.
- (she): From Middle English a, ha, unstressed variant of heo, hie, hi, from Old English hēo, hīo, hī feminine of hē (“he”).
- (they): From Middle English a, ha, unstressed variant of hie, hi, from Old English hīe, hī plural of hē (“he”).
- (it): From Middle English a, ha, unstressed variant of he, heo, from Old English hit (“it”).
- (I): From Middle English variant of the word I.
- A meaningless syllable; ah.
Variant spelling of ah.
- (archaic, slang) Of.
- The name of John a Gaunt.
- Often attached without a hyphen to preceding word.
From Middle English, contraction of of.
- (chiefly Scotland) All. [First attested from 1350 to 1470.]
- Distance from leading edge to aerodynamic center.
- specific absorption coefficient
- specific rotation
- allele (recessive)
(upper case, lower case a)
- A frame
- ABC, A.B.C.
- A to Z
(upper case, lower case a)
From Middle English and Old English upper case letter A and split of Middle English and Old English upper case letter Æ.
- Old English upper case letter A from 7th century replacement by Latin upper case letter A of the Anglo-Saxon Futhorc letter ᚪ (a, “āc”), derived from Runic letter ᚫ (a, “Ansuz”).
- Old English upper case letter Æ from 7th century replacement by Latin upper case ligature Æ of the Anglo-Saxon Futhorc letter ᚫ (æ, “æsc”), also derived from Runic letter ᚫ (a, “Ansuz”).
- The highest rank on any of various scales that assign letters.
- We assign each item inspected a rating from A through G, depending on various factors.
- Bond rating
- (education) The highest letter grade assigned (disregarding plusses and minuses).
- I was so happy to get an A on that test.
- (music) A tone three fifths above C in the cycle of fifths; the sixth tone of the C major scale; the first note of the minor scale of A minor; the reference tone that occurs at exactly 440 Hz; the printed or written note A; the scale with A as its keynote.
- Orchestras traditionally tune to a concert A.
- (medicine) A blood type that has a specific antigen that aggravates the immune response in people with type B antigen in their blood. They may receive blood from type A or type O, but cannot receive blood from AB or B.
- My blood type is A negative.
- (chemistry) Mass number.
- (logic) A universal affirmative suggestion.
- acoustic source
- actual weight of an aircraft
- (historical) adulterer, adulteress
- Alaska Steamship Company
- Alcoa Steamship Company
- allele dominant
- alveolar gas
- American Stock Exchange
- ammunition examiner
- Anchor Line
- aspect ratio
- Assembly Bill
- Smallest of the brassiere cup sizes.
- Chemical activity.
- first van der Waals constant
- Fraunhofer line for oxygen
- (aviation) hail
- (in newspaper stock listings) includes extras
- linear acceleration
- mean sound absorption coefficient
- Shoe size narrower than B
- (baseball) Single A league, one of the lowest professional leagues.
- Total acidity.
- (highest rank, grade, music): From the initial position of the letter A in the English alphabet.
- (blood type): From A antigen
- (vehicle-distinguishing signs): From Australia
- Eye dialect spelling of have.
- plural form of -um
- plural form of -on
- Because the regular pluralization in English involves adding -s or -es, English words derived from a Latin where the Latin would pluralize from -on or -um to -a do not always do so in English. Usage of -a instead of -s differs between words: sometimes the two are interchangeable (e.g. memorandums/memoranda, polyhedrons/polyhedra), sometimes one is far more common than the other (e.g. neurons over neura, automata over automatons), and sometimes one is completely absent from usage (e.g. bacteria over bacteriums, dendrons over dendra)
- (Geordie) Same as -er in Standard English.
- (slang) Used to replace -er in nouns.
Possibly due to the propensity in some non-rhotic dialects to pronounce words ending in -er as if they ended in an -a.
(plural -ae or -æ)
From Latin -a.
- (slang) Alternative form of -'ve.
Shortened version of verb have.
- Added for metrical reasons to poetry and verse
Added to lines of poetry and verse to maintain metrics.
- (slang) clitic form of o'
Shortened version of preposition of.
- (informal) To.
Shortened version of verb to.
- -mab is the base suffix common to all monoclonal antibodies
The vowel of rat
Various, often difficult to determine. Used in Middle English since 14th century.
Sometimes borrowed from French à (“(various prepositions)”), as in vis-à-vis, sometimes reduced from of. Other words may be established on these models, as in jack-a-napes. May be spelled differently, with same schwa pronunciation, as in o' or Cockney (from Cockeney); other early form in ragamuffin and cock-a-leekie.
- (slang) Australian dollar
(plural A*'s or A*s)
- absolute temperature
- absorbance; absorbancy
- academy; academician
- accusative case
- acre; acres
- A; a.
- age; aged
- air branch
- aircraft; airplane
- America; American; Americanize; Americanization
- (biblical) Amos, the book of
- amphibian; amphibious
- ana; anna
- annō (in the year)
- annus (a year)
- ante (before)
- (military) assault, as on a badge
- associate; association
- atomic; atomic weight
- avancé (fast)
Capital Roman A has been used in place of capital Greek Α (alpha).
- Alternative form of A-.
It is more common to type this term spelled with the hyphen-minus sign (-).See the main entry, that is spelled with that symbol: A-. This entry in particular is an alternative form spelled with the minus sign (−).
- Alternative spelling of a (all). [First attested from 1350 to 1470.]
- Euphemistic spelling of ass.
- (metrology) Symbol for the attoohm, an SI unit of electrical resistance equal to 10−18 ohms.
- (archaic) Alternative form of Aeaea.
a - Computer Definition