what type of word is my

The word "my" is primarily a possessive determiner (also called a possessive adjective). It is used to indicate possession or relationship to the speaker and modifies a noun that follows it, as in "my car" or "my name." It does not stand alone as a pronoun typically does, but functions to show that something belongs to or is associated with the speaker. Additionally, "my" can sometimes be used as an interjection to express surprise or amazement, for example, "My, what big teeth you have!" In summary, "my" is mainly a possessive determiner modifying a noun, and occasionally an interjection expressing surprise or emotion.