Somehow entrap guardian (6)
I believe the answer is:
parent
'guardian' is the definition.
(thesaurus)
'somehow entrap' is the wordplay.
'somehow' is an anagram indicator.
'entrap' with letters rearranged gives 'PARENT'.
(Other definitions for parent that I've seen before include "Author" , "The company of which others are subsidiaries" , "Raise" , "person responsible for children" , "One with children" .)