Charge to restrict right on-line nuisance (5)
I believe the answer is:
troll
'nuisance' is the definition.
(I know that troll is a type of nuisance)
'charge to restrict right on-line' is the wordplay.
'charge' becomes 'tol' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'to restrict' is an insertion indicator (inserted letters are restricted or contained).
'right' becomes 'r' (common abbreviation).
'on' means one lot of letters go next to another.
'line' becomes 'l' (used when specifying particular lines from a poem).
'tol' going around 'r' is 'trol'.
'trol'+'l'='TROLL'
Can you help me to learn more?
(Other definitions for troll that I've seen before include "Online annoyance" , "Draw baited line, to lure fish" , "Internet provoker; ugly being" , "Scandinavian monster" , "Fish with a moving bait" .)