A, a[ ey ]

noun, plural A’s or As, a’s or as.

the first letter of the English alphabet, a vowel.
any spoken sound represented by the letter A ora, as in bake, hat, father, or small.
something having the shape of an A.
a written or printed representation of the letter Aor a.
a device, as a printer’s type, for reproducing the letter A or a.

IDIOMS FOR A, 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.