A's

noun pl. A's , a's

1. the first letter of the English alphabet: from the Greek alpha, a borrowing from the Phoenician
2. any of the speech sounds that this letter represents, as, in English, the vowel (a) of hat, (ä) of father, (ā) of bake, or (ô) of call
3. a type or impression for a or A
4. the first in a sequence or group
5. an object shaped like

adjective

1. of a or A
2. first in a sequence or group
3. shaped like