Stash rest EEC wasted (7)
I believe the answer is:
secrete
'stash' is the definition.
(thesaurus)
'rest eec wasted' is the wordplay.
'wasted' indicates an anagram.
'rest'+'eec'='resteec'
'resteec' anagrammed gives 'SECRETE'.
(Other definitions for secrete that I've seen before include "Hide or conceal an object" , "Place out of sight, hide" , "Hide away" , "Release bodily fluid" , "Hide; as gland does" .)