Attitude entertains small group of friends (5)
I believe the answer is:
posse
'group of friends' is the definition.
(I've seen this before)
'attitude entertains small' is the wordplay.
'attitude' becomes 'pose' (attitude can mean a pose or stance).
'entertains' indicates putting letters inside.
'small' becomes 's' (abbreviation - e.g. clothes size).
'pose' going around 's' is 'POSSE'.
(Other definitions for posse that I've seen before include "Group of friends together" , "Sheriff's assistants" , "Sheriff's party" , "Sheriff's band of men" , "Group aiding lawman" .)