Meaning of "a" in Essential American English Dictionary

a

determiner us unstressed /ə/ us stressed // also an unstressed /ən/ stressed /æn/

A1 used before a noun to mean one thing or person:

I need a car.
Can I have an apple?

A1 every or each:

Take one pill three times a day.

A1 used to say what job someone does:

She’s a mechanic.

(Definition of “a” from the Webster's Essential Mini Dictionary © Cambridge University Press)