Inquiry
Part of speech: noun
Definition: The act of inquiring; a seeking of information by asking questions; interrogation; a question or questioning. Search for truth, information, or knowledge; examination of facts or principles; research; investigation; as, physical inquiries.
Example sentence: Time and again, we have found the 'idle' truths arrived at through the process of inquiry to be of the greatest moment for practical human affairs.
Interrogation
Part of speech: noun
Definition: The act of interrogating or questioning; examination by questions; inquiry.A question put; an inquiry.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.
Example sentence: Many of Bush's defenders have praised him for keeping the country safe since Sept. 11, 2001. He deserves that praise, and I'm perfectly happy to defend most of his surveillance, interrogation and counterterrorism policies against his critics.