poser

noun ! Definition from Wiktionary (CC BY-SA). Pronunciation from Wiktionary, via Kaikki.org. More about poser at Wordnik → Where our words come from →

1. A particularly difficult question or puzzle.
2. Someone who asks a question or sets a problem.

   Even as a child, she was a habitual poser of difficult questions.

3. Someone who, or something which, poses; a person who sets their body in a fixed position, such as for photography or painting.