Name of words with multiple meanings? [duplicate]
There is the linguistic term polyseme for a word that has several meanings. The Greek word element poly- means much/many, the Greek word element -seme means sign, from Greek sêma sign. The phenomenon that words or in general signs can have a lot of meanings is called polysemy.
Wikipedia has an article on polysemy. Wikipedia, polysemy
Specialists distinguish the case that a word has a basic meaning and acquires various uses in different fields such as the word point. All uses of "point" can be understood as a metaphoric transfer into various areas.
There is the other case as can be seen in the word date which has meanings that come from the Latin verb dare to give and the verb form datum given. "date" as a fruit has another source. Actually we have two words, date 1 and date 2, but words can get the same spelling and pronunciation in the course of time.
The term you're looking for is "polysemic."
polysemic (also polysemous): having more than one meaning; having multiple meanings. E.g. "Set" is a good example of a polysemic word.
The two examples you provided are Homonyms (the words are pronounced the same in both cases, but mean different things), but the more general term for what you are asking is Homographs (same spelling, but the pronunciation can differ). An example of this is Bow- to bend over, or used in archery. There are also Homophones where the spelling is different, but the pronunciation is the same (eg, red and read).
You may also be interested in auto-antonyms which are words which have two meanings but the meanings are opposites. For example left can mean departed or remaining, and sanction can mean permit or punish.