Verb (5-dan, む, intransitive)
1. to be dented; to be indented; to yield; to give; to sink; to collapse; to cave in
車体の前面が少しへこんでいた。The front of the car body was slightly dented.
2. to be beaten; to be overwhelmed; to yield; to give in; to give up
3. to be disheartened; to feel down; to feel depressed
そうは言っても僕は少しへこんでいた。Even so, I was a little disheartened.
4. to suffer a loss; to lose