Inch from shelf lecturer lopped off (4)
I believe the answer is:
edge
'inch' is the definition.
(I know that inch can be written as edge)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for edge that I've seen before include "Move little by little to the border" , "Bite" , "Cutting side as of knife, or margin" , "Guitarist with U2" , "Border, fringe" .)