Spotted one being rushed outside (5)
I believe the answer is:
spied
'spotted' is the definition.
('spy' can be a synonym of 'spot')
'one being rushed outside' is the wordplay.
'one' becomes 'i' (Roman numeral**).
'being rushed' becomes 'sped' (I've seen this before).
'outside' is an insertion indicator.
'i' placed into 'sped' is 'SPIED'.
(Other definitions for spied that I've seen before include "Watched secretly" , "Seen" , "Was a secret agent" , "Spotted" , "Caught sight of" .)