Small holiday complex for rascal (5)
I believe the answer is:
scamp
'for rascal' is the definition.
(synonyms)
'small holiday complex' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'holiday complex' becomes 'camp' (camp site).
's'+'camp'='SCAMP'
(Other definitions for scamp that I've seen before include "Little Devil" , "little monkey" , "Impish child" , "Scoundrel" , "Troublemaker" .)