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The first letter of the English and most other alphabets, is frequently used as an abbreviation, (q. v.) and also in the marks of schedules or papers, as schedule A, B, C, &c. Among the Romans this letter was used in criminal trials. The judges were furnished with small tables covered with wax, and each one inscribed on it the initial letter of his vote; A, when he voted to absolve the party on trial; C, when he was for condemnation; and N L, (non liquet) when the matter did not appear clearly, and be desired a new argument.

the first letter in our alphabet, its corresponding symbol standing first also in many other alphabets derived from the Phoenician. It originated in the hieroglyphic picture of an eagle (Old Egyptian ahom), the cursive hieratic form of which was the original of the Phoenician aleph, an ox, from a fancied resemblance to its head and horns.--A, as a note in music, is the major sixth of the scale of C; A1, the symbol by which first-class vessels are classed in Lloyd's Register of British and Foreign Shipping, hence first-rate.

the indefinite article, a broken-down form of An, and used before words beginning with the sound of a consonant. [An was a new development, after the Conquest, of the A.S. numeral án, one.]

ä or [=a], a prep., derived from the old prep. on, and still used, as a prefix, in afoot, afield, apart, asleep, nowadays, twice-a-day; also with verbal nouns, as a-building, to be a-doing, to set a-going. It is now admitted only colloquially. [Short for A.S. an, a dialectic form of on, on, in, at. See PREFIXES.]

ä, a dialectic corruption of he or she, as in quotha, (Shak.) 'A babbled of green fields.'--A, usually written a', Scotch for all; A, a form of the L. prep. ab, from, of, used before consonants, as in Thomas à Kempis, Thomas à Becket, &c.

Abbreviation for anode.

Abbreviations for ana, of each.

Letter (pl. As A\'s, Aes). (Mus.) note, and the corresponding scale. (In argument) first imaginary person or case. (Alg.) first known quantity. (Naut.) A1 (a wun), first-class ship in Lloyd\'s register; excellent, best, (colloq.). (Naut.) AE, third-class ship at Lloyd\'s. Abbreviations (1): ab, A.U.C. (urbe condita); able, A.B. (-bodied); acting, as A.A.Q.M.G. (assistant quartermaster general); assistant, as A.A.G. (adjutant general), A.Q.M.G. (quartermaster general); adjutant, as A.G. (general); aide, A.D.C. (-de-camp); anno, as A.D. (domini), A.H. (hegirae); ante, as a.m. (meridiem); army, as A.S.C. (service corps); Associate, as A.R.A. (Royal Academy); authorized, A.V. (version). Abbreviations (2): ab init., ab initio; Abp, Archbishop; a/c., account; Adm., Admiral; advt, advertisement; aet., aetatis; Ala., Alabama; Alas., Alaska; Alban., Bishop of St Alban\'s; Ariz., Arizona; Ark., Arkansas; arr., arrives.

On, to, towards, into, in. Mostly now written as pref., or oftener omitted than expressed, or confused w. A. On: abed, afoot. To: ashore. Towards: aback, afar, aside. Into: apart, asunder. In: now-a-days, twice a day; w. vbl nouns, passively, a-building, actively, was (a-) fighting, and esp. w. go, set, as he went a begging, they set the bells a ringing. [old English]

Abbreviation for anterior and anode.

Symbol for argon.

An abbreviation for anode and anterior.

The symbol for argon.

A symbol used to denote total acidity.

The first letter of the alphabet in most languages; –the indefinite article, signifying one or any, placed before nouns of the singular number denoting an individual object, before collective nouns , and also before plural nouns when the adjective few or the phrase great many is interposed. It is a contraction of the Anglo-saxon an, or ane, one, and is substituted for an before all words beginning with a consonant sound, except words beginning with the sound of h and having the accent on any other syllable than the first; as, a table, a woman, a year. A sharp, the name of the musical tone intermediate between A and B. A flat, the name of a tone intermediate between A and G.

The first letter of the alphabet. A, an article set before nouns of the singular number; a man, a tree; Before a word beginning with a vowel, it is written an, as, an ox; A is sometimes a noun, as, great A; A is placed before a participle, or participial noun; a hunting, a begging; A has a signification denoting. proportion, the landlord has a hundred a year.