Assign vs Invest - What's the difference?

Assign is a synonym of invest.

In obsolete|lang=en terms the difference between assign and invest

is that assign is (obsolete) a thing relating or belonging to something else; an appurtenance while invest is (obsolete) to put on (clothing).

As verbs the difference between assign and invest

is that assign is (lb) to designate or set apart something for some purpose while invest is (dated) to clothe or wrap (with garments).

As nouns the difference between assign and invest

is that assign is an assignee while invest is (meteorology) an unnamed tropical weather pattern "to investigate" for development into a significant (named) system