Definition of "interrogative" [in•ter•rog•a•tive]

• Asking a question or being of the nature of a question: an interrogative raising of the eyebrows. (adjective)
• Of, relating to, or being an element or construction used to ask a question: an interrogative adverb; an interrogative particle. (adjective)
• A word or form used to ask a question. (noun)
• A sentence or an expression that asks a question. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "-- When are they called interrogative pronominal adjectives?"
• "The language of vainglory, of indignation, pity and revengefulness, optative: but of the desire to know, there is a peculiar expression called interrogative; as, What is it, when shall it, how is it done, and why so?"
• "I'm already very pleased by a bit of information from the Abaza section:Abaza and Abkhaz questions are very unusual in that they choose rightward question movement; that is, the interrogative pronoun appears at the end of the verb, and since the verb is usually the last word of the phrase, these wh-words, as they are called, appear phrase finally."