Cut right in middle of grotto (5)
I believe the answer is:
carve
'cut' is the definition.
(carving is a kind of cutting)
'right in middle of grotto' is the wordplay.
'right' becomes 'r' (common abbreviation).
'in middle of' is an insertion indicator.
'grotto' becomes 'cave' (I've seen this before).
'r' inserted within 'cave' is 'CARVE'.
(Other definitions for carve that I've seen before include "Cut meat with sharp knife" , "Slice (joint)" , "produced by desire, with a shifting to the left" , "Chisel, sculpt" , "Cut (cooked meat)" .)