1: not any particular or certain one of a class or group:
2: a certain; a particular:
3: another; one typically resembling:
4: one (used before plural nouns that are preceded by a quantifier singular in form): a hundred men (compare hundreds of men); a
dozen times (compare dozens of times).
5: indefinitely or nonspecifically (used with adjectives expressing
number):
6: one (used before a
noun expressing quantity):
1: a man; a chemical; a house.
2: one at a
time; two of a kind; A Miss Johnson called.
3: a Cicero in eloquence; a
Jonah.
5: a great many years; a few stars.
6: a
yard of ribbon; a score of times.