Shelter in special surroundings for a nap (5)
I believe the answer is:
sleep
'for a nap' is the definition.
(synonyms)
'shelter in special surroundings' is the wordplay.
'shelter in' becomes 'lee' (as in lee side, the side sheltered from wind. I am not sure about the 'in' bit.).
'special' becomes 'sp' (abbreviation).
'surroundings' means one lot of letters goes inside another.
'lee' put within 'sp' is 'SLEEP'.
Can you help me to learn more?
(Other definitions for sleep that I've seen before include "Natural state of unconscious rest" , "Shut-eye" , "Drop off" , "Produced (egg)" , "Snooze" .)