- an instance of questioning
"there was a question about my training"
"we made inquiries of all those who were present"

- formal systematic questioning

- a sentence of inquiry that asks for a reply
"he asked a direct question"
"he had trouble phrasing his interrogations"

- a transmission that will trigger an answering transmission from a transponder

1. The act of interrogating or questioning; examination by questions; inquiry.

2. A question put; an inquiry.

3. A point, mark, or sign, thus [?], indicating that the sentence with which it is connected is a question. It is used to express doubt, or to mark a query. Called also interrogation point.

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In works printed in the Spanish language this mark is not only placed at the end of an interrogative sentence, but is also placed, inverted [as thus (&iques;)], at the beginning.