Small nuisance in country (5)
I believe the answer is:
spain
'country' is the definition.
(Spain is an example)
'small nuisance' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'nuisance' becomes 'pain' ('pain' can be a synonym of 'nuisance').
's'+'pain'='SPAIN'
'in' acts as a link.
(Other definitions for spain that I've seen before include "European country" , "country of mostly dry mountains, going by air" , "EU country" , "holiday destination?" , "Catholic country" .)