A word or phrase used to ask questions.

प्रश्नवाचक

English Usage: The word "who" is an interrogative.

Hindi Usage: "कौन" एक प्रश्नवाचक है।

Relating to or characteristic of questions.

प्रश्नात्मक

English Usage: She had an interrogative tone when she asked him.

Hindi Usage: जब उसने उससे पूछा तो उसकी आवाज प्रश्नात्मक थी।