1. adjective /ˌɪntəˈrɒɡətɪv/
Asking or denoting a question; pertaining to inquiry; questioning: as, an interrogative phrase, pronoun, or point; an interrogative look or tone of voice.
The regular place of the interrogative word, of whatever kind, is at the beginning of the sentence, or as near it as possible.
Syn: examining, inquiring, investigative
2. noun /ˌɪntəˈrɒɡətɪv/
Wikipedia foundation.