Crevice
Crack, Gap, Opening
noun
A crevice interval is an area with a crevice or crack.
The reading for 隙 is the one you learned with the kanji and the 間 is the 間に合う reading.
二台の自販機の隙間に、小銭が2-3枚落ちているのを見つけました。
I found a few coins in the gap between two vending machines.
網戸の隙間から小さな虫が入ったみたい。
It seems a small bug got in through a gap in the screen.
ふと窓際を見ると、カーテンの隙間から、誰かがこちらを覗いていた。
When I happened to glance toward the window, I saw someone peering at me through a gap in the curtains.