Interrogative
Part of speech: noun
Definition: A word (pronoun, pronominal adjective, or adverb) implying interrogation, or used for asking a question: why, who, when, etc. A question; an interrogation.
Part of speech: adjective
Definition: Asking or denoting a question; pertaining to inquiry; questioning: as, an interrogative phrase, pronoun, or point; an interrogative look or tone of voice.
Interrogatory
Part of speech: noun
Definition: A formal question submitted to opposing party to answer, generally governed by court rule.