What part of speech is the word whom?

"Whom" is a pronoun. More specifically, it is an object pronoun, used as the object of a verb or preposition.

Here's why:

* Pronoun: It replaces a noun (a person, place, or thing).

* Object pronoun: It acts as the receiver of the action.

Example:

"To whom did you give the book?"

In this sentence, "whom" is the object of the preposition "to."

Tip: If you can substitute "him" or "her" for "whom," then it is used correctly.