Nettle or grass? (4)
I believe the answer is:
nark
I believe this is a double definition.
'nettle' is the first definition.
('nark' can be a synonym of 'nettle')
'grass?' is the second definition.
(thesaurus)
'or' acts as a link.
(Other definitions for nark that I've seen before include "Annoy; police informer" , "Cause minor annoyance" , "Habitual grumbler" , "cause irritation" , "Police spy" .)