Synonyms for Interrogative (same or very similar meaning)
WordNet sense 1 (some linguists consider interrogative sentences to constitute a mood):
interrogative mood
WordNet sense 2 (a sentence of inquiry that asks for a reply):
interrogation, question, interrogative sentence
WordNet sense 3 (relating to the use of or having the nature of an interrogation):
interrogatory, asking
From the ODE community, based on WordNet
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