Bishop, in essence? Android (5)
I believe the answer is:
robot
'android' is the definition.
(I've seen this before)
'bishop in essence?' is the wordplay.
'bishop' becomes 'b' (abbreviation used in chess).
'in' is an insertion indicator.
'essence?' becomes 'root'.
'b' put into 'root' is 'ROBOT'.
(Other definitions for robot that I've seen before include "Automaton or sci-fi creature" , "Unpaid worker" , "Man-made man - man-made machine" , "Computer-controlled machine" , "Mechanical worker" .)