noun
General term for a person who helps with work, tasks, or activities. Can be used in many settings, from offices to personal projects.
彼は料理の助手としてレストランで働いている。
He works at the restaurant as a kitchen assistant.
引っ越しの助手を友人に頼んだ。
I asked a friend to help with the move.
noun
research assistant; teaching assistant
Specifically an assistant to a professor or researcher in an academic setting. Often implies a formal position at a university or research institution.
大学院生が教授の助手として実験を手伝っている。
The graduate student is helping with experiments as the professor's research assistant.