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the blood group whose red cells carry the A antigen

a metric unit of length equal to one ten billionth of a meter (or 0.0001 micron); used to specify wavelengths of electromagnetic radiation

the basic unit of electric current adopted under the Systeme International d'Unites; "a typical household circuit carries 15 to 50 amps"

the blood group whose red cells carry the A antigen

the basic unit of electric current adopted under the System International d'Unites; "a typical household circuit carries 15 to 50 amps"

a metric unit of length equal to one ten billionth of a meter (or 0.0001 micron); used to specify wavelengths of electromagnetic radiation

The first letter of the English and of many other alphabets. The capital A of the alphabets of Middle and Western Europe, as also the small letter (a), besides the forms in Italic, black letter, etc., are all descended from the old Latin A, which was borrowed from the Greek Alpha, of the same form; and this was made from the first letter (/) of the Phoenician alphabet, the equivalent of the Hebrew Aleph, and itself from the Egyptian origin. The Aleph was a consonant letter, with a guttural breath sound that was not an element of Greek articulation; and the Greeks took it to represent their vowel Alpha with the a sound, the Phoenician alphabet having no vowel symbols.

The name of the sixth tone in the model major scale (that in C), or the first tone of the minor scale, which is named after it the scale in A minor. The second string of the violin is tuned to the A in the treble staff. -- A sharp (A/) is the name of a musical tone intermediate between A and B. -- A flat (A/) is the name of a tone intermediate between A and G.

An adjective, commonly called the indefinite article, and signifying one or any, but less emphatically.

In; on; at; by.

A barbarous corruption of have, of he, and sometimes of it and of they.

An expletive, void of sense, to fill up the meter

In process of; in the act of; into; to; - used with verbal substantives in -ing which begin with a consonant. This is a shortened form of the preposition an (which was used before the vowel sound); as in a hunting, a building, a begging.

The first letter of the English and of many other alphabets. The capital A of the alphabets of Middle and Western Europe, as also the small letter (a), besides the forms in Italic, black letter, etc., are all descended from the old Latin A, which was borrowed from the Greek Alpha, of the same form; and this was made from the first letter (/) of the Phoenician alphabet, the equivalent of the Hebrew Aleph, and itself from the Egyptian origin. The Aleph was a consonant letter, with a guttural breath sound that was not an element of Greek articulation; and the Greeks took it to represent their vowel Alpha with the a sound, the Phoenician alphabet having no vowel symbols.

The name of the sixth tone in the model major scale (that in C), or the first tone of the minor scale, which is named after it the scale in A minor. The second string of the violin is tuned to the A in the treble staff. -- A sharp (A/) is the name of a musical tone intermediate between A and B. -- A flat (A/) is the name of a tone intermediate between A and G.

An adjective, commonly called the indefinite article, and signifying one or any, but less emphatically.

In; on; at; by.

An expletive, void of sense, to fill up the meter

In process of; in the act of; into; to; - used with verbal substantives in -ing which begin with a consonant. This is a shortened form of the preposition an (which was used before the vowel sound); as in a hunting, a building, a begging.

barbarous corruption of have, of he, and sometimes of it and of they.

One; any: used before words beginning with a consonant or the sound of h.

To; in; into; as, once a month; to go a-Maying.

Chemical symbol of the element argon.

Abbreviation for accommodation, anode, anterior, and total acidity.

Prefix, denoting absence of.

Used at one time before participles, as in "She lay a dying." It is now admitted only colloquially.

The name of the first letter of the alphabet; the indefinite article, used before consonant-sounds.

Article or adjective. One; any; each; before a vowel, an.

On, awry, out, off, from, to; also a mere intensive; as, adown, athirst.

Not, in-, un; in words derived from the Greek; as, achromatic. an.

A vowel, is the first letter of the alphabet of all the known languages, except the Ethiopic, in which it is the thirteenth, and the Runic, in which it is the tenth. It has, in English, four distinct sounds: the long or slender, as in place, fate, cake; the short, as in cat, china, fancy; the open, or Italian, as in father, cast, glass; and the broad, as in wall, appal, which is shortened in squad, what.

A contraction of the Anglo-Saxon an or ane, is called the indefinite article, implying one, any, someone, and is used before nouns of the singular number, as a man, o tree. Before a word beginning with a vowel or a silent h, it is, for the sake of euphony, changed into an, as an owl, an heir.

Has many significations in our old writers and in our provincial dialects, of which the following are some: ah, he, they, all, on, have, one, always, yes, even, &c. It has also a peculiar signification, denoting proportion, or each, as a hundred a year, a pound, a man. It is also sometimes placed before a participle, as gone a-hunting, come a-begging, the house is a-building.

As a prefix to many English words, is equivalent to the prepositions in or on. as in asleep, alive, afoot, aground. A is also a prefix of Latin and Greek words, and means, when prefixed to Latin words. away from, as avert, to turn away from, vert meaning to turn; and when prefixed to Greek words, it means not or without, as atom, what cannot be divided, tom coming from a word meaning to cut.

In abbreviations, stands for artium, anno, ante, &c., as, A.M., artium magister, master of arts ; A.D., anno Domini, in the year of Our Lord; A.M., antemeridiem, before noon. Among the Romans, A.U.C. stood for anno urbis conditoe, from the year of the building of the city, or Rome. A, or AA, in pharmacy, are abbreviations of the Greek word ana, signifying of each.

In Music is the nominal of the sixth note in the natural diatonic scale, and corresponds to the la of Guido. It is also the name of one of the two natural moods; and it is the open note of the second string of the violin, by which the other strings are tuned and regulated.

The first letter of the alphabet in most languages; an adjective of number, signifying one; the indefinite article-used before adjectives or nouns that begin with a consonant or with the sound of a consonant; an Anglo-Saxon prefix signifying at, to, in, or on; a Greek prefix, also its form an, signifying without, not; a Latin prefix, with its forms ab and abs, signifying from or away.