To Let Someone Escape
To Let Someone Go, To Set Someone Free
transitive verb, godan verb
You know how 逃げる means "to escape"? This is the transitive version, so it means to let someone escape, to let someone go, or to set someone free. You know this because you'd want to let everyone escape when the place is filled with gas (がす).
逃がす is often about purposely letting someone or something go — like setting a bird free or letting a captive escape quietly. But it can also be used in more unintentional and regretful situations, like failing to catch a criminal or missing a big opportunity.
You learned the に reading for this kanji when you learned 逃げる but here’s another mnemonic to help you remember:
You decided to let someone escape because they were on their knees (に) begging you to set them free.
あの犯人を逃がすことはできない。
We can’t let the criminal escape.
この施設に捕らえられている人質を逃がすために潜入しました。
I've infiltrated this facility to set free the hostages who are being held here.
いいカモだったのに、逃がしちゃったね。
He was a real stitting duck, but we let him go.