Bishop with complete stoop (4)
I believe the answer is:
bend
'stoop' is the definition.
(thesaurus)
'bishop with complete' is the wordplay.
'bishop' becomes 'b' (abbreviation used in chess).
'with' means one lot of letters go next to another.
'complete' becomes 'end' (I've seen this before**).
'b'+'end'='BEND'
(Other definitions for bend that I've seen before include "submit" , "elbow" , "Crouch" , "Knot; heraldic stripe" , "Form a curve" .)