Silent lionesses, wild (9)
I believe the answer is:
noiseless
'silent' is the definition.
(thesaurus)
'lionesses wild' is the wordplay.
'wild' indicates an anagram.
'lionesses' anagrammed gives 'NOISELESS'.
(Other definitions for noiseless that I've seen before include "unsound?" , "Lionesses (anag) - making no sound" , "Silent, quiet" , "Mum" , "with a silencer?" .)