Timid or faint-hearted; lacking boldness or courage. Often used as '気弱な人' (a timid person).
彼は初めての面接で少し気弱に見えた。
He seemed a bit timid at his first interview.
気弱な性格だから、すぐに自信を失ってしまう。
Because of his timid personality, he quickly loses confidence.
気弱にならないように、前もって準備しておいた。
I prepared in advance so I wouldn't get timid.