Goblin right in charge (5)
I believe the answer is:
troll
'goblin' is the definition.
(I've seen this before)
'right in charge' is the wordplay.
'right' becomes 'r' (common abbreviation).
'in' means one lot of letters goes inside another.
'charge' becomes 'toll' (toll is a kind of charge).
'r' placed into 'toll' is 'TROLL'.
(Other definitions for troll that I've seen before include "ugly cave-dweller" , "Internet provoker; ugly being" , "Supernatural cave-dweller" , "Ugly character from Norse legend" , "In Scandinavia, a mythical giant or dwarf" .)