Fall outing (4)
I believe the answer is:
trip
I believe this clue is a double definition.
'fall' is the first definition.
(as in tripping over)
'outing' is the second definition.
(I've seen this before)
(Other definitions for trip that I've seen before include "Stumble - excursion" , "Pleasure excursion" , "Jaunt" , "a result of drug-taking" , "Journey; make a mistake" .)