noun
A noun for the act of asking a question or posing a query; can be used in both casual and formal contexts.
彼の問いかけに誰も答えなかった。
No one answered his question.
先生は生徒たちに問いかけを投げかけた。
The teacher posed a question to the students.
Compound of 問い (とい, 'question', the continuative form of 問う) + かけ (かけ, 'hanging, putting forth', the continuative form of 掛ける). Literally 'question-putting'.