homonym

two words are homonyms if they are pronounced or spelled the same way but have different meanings

• homograph — two words are homographs if they are spelled the same way but differ in meaning (e.g. fair)
• homophone — two words are homophones if they are pronounced the same way but differ in meaning or spelling or both (e.g. bare and bear)

• word — a unit of language that native speakers can identify