Having many sides; polygonal / Having many aspects

A certain number of / Great in number; very numerous; a large number of

The fact or quality of having many sides or facets.

(poetic) many other, most other (followed by singular noun)

(informal) many happy returns

(nonstandard) Many a time; often.

(mathematics, of a function) Having the property that the same argument may yield multiple values, but different arguments never yield the same value.

(mathematics, logic, of a relationship between two sets) having the property that many elements of one set may be assigned by the relationship to one element in the other set, and that a given element in the first set can be assigned by only one member of the second set.

Excessive (used with countable nouns).

Involving many hands.