Relaxes in a forest stream (5)
I believe the answer is:
rests
'relaxes' is the definition.
(I've seen this before)
'in a forest stream' is the wordplay.
'in' indicates the answer is hidden within the clue.
'RESTS' is hidden in the letters of 'forest stream'.
(Other definitions for rests that I've seen before include "Takes a break" , "holidays" , "Relaxes; supports" , "Relaxes, sleeps" , "Musical pauses" .)