Penniless, goes back to pick up penny (8)
I believe the answer is:
strapped
'penniless' is the definition.
(informal term for being short of money)
'goes back to pick up penny' is the wordplay.
'goes' becomes 'departs' ('depart' can be a synonym of 'go').
'back' says the letters should be written in reverse.
'to pick up' is an insertion indicator.
'penny' becomes 'p'.
'departs' backwards is 'straped'.
'straped' placed around 'p' is 'STRAPPED'.
(Other definitions for strapped that I've seen before include "Without, or very short of, money" , "beaten" , "broke" , "not generating enough cash?" , "affected by shortage" .)