Adaptable flexible relatives (9)
I believe the answer is:
versatile
'adaptable' is the definition.
(thesaurus)
'flexible relatives' is the wordplay.
'flexible' indicates anagramming the letters (I've seen this in other clues).
'relatives' anagrammed gives 'VERSATILE'.
(Other definitions for versatile that I've seen before include "Adaptable like relatives" , "Having many uses" , "Capable of many functions" , "Adaptable kind of relatives" , "Resourceful; relatives (anag.)" .)