in the grass; behind the grass; shadow of the grass
Refers to a place hidden or obscured by tall grass. Often used in contexts of hiding or being concealed.
A cat jumped out from the grass.
彼は草陰に隠れて様子をうかがった。
He hid in the grass and watched the situation.
Compound of 草 (くさ, 'grass') and 陰 (かげ, 'shade' or 'hidden place'). The reading くさかげ is a straightforward combination.