This is a word that has multiple meanings and is spelled in the same way for both meanings. Example: 'Board' meaning a piece of wood, and 'board' as in a group of people are examples.

what kind of word are you looking for?

Short answer: homonym

Long answer:

Homograph=same spelling, different sound, different meaning

Homophone=different spelling, same sound, different meaning

Homonym=same spelling, same sound, different meaning

BUT nowadays, homonym is losing the strict definition of the word and is being used for homographs and homophones as well. It would still probably be best to refer to this as a homonym in this instance, since that is what it technically is.