Three questions must be separated. Has a word been newly assigned a conventional sense? Has a sense become established through transfer from a previous convention? Does one form have more than one independently assigned meaning?
A new coinage, an established transferred term, and a homonym present different accounts of assignment. They cannot be reduced to one vague statement that a word happens to have several meanings.
This distinction matters because a new recognized assignment is not automatically identical with a temporary figurative departure from an assigned sense.