Person on outdoor holiday chasing small beetle (7)
I believe the answer is:
scamper
'beetle' is the definition.
(beetle can mean to scamper around)
'person on outdoor holiday chasing small' is the wordplay.
'person on outdoor holiday' becomes 'camper' (someone camping).
'chasing' is a charade indicator (letters next to each other).
'small' becomes 's' (abbreviation - e.g. clothes size).
'camper' put after 's' is 'SCAMPER'.
(Other definitions for scamper that I've seen before include "Run along quickly" , "Run with quick light steps" , "Scurry, scuttle" , "Skip about briskly" , "Run quickly and lightly" .)