chIl means "lose" in the sense of "misplace, be unable to find, lose track of." It can be used for misplacing your keys, but also for things like losing the signal of something you've been tracking. "Lose" in the sense of "no longer have (presumably permanently)", as in "we've lost a lot of soldiers" is a different word: weS. This verb means "lose" in the sense of "undergo a reduction of" or "suffer a reduction of", as in "he lost a lot of blood".