I bumped into flipping object (4)
I believe the answer is:
item
'object' is the definition.
(I've seen this before)
'i bumped into flipping' is the wordplay.
'bumped into' becomes 'met' (I've seen this before).
'flipping' is a reversal indicator.
'met' backwards is 'tem'.
'i'+'tem'='ITEM'
(Other definitions for item that I've seen before include "newspaper article" , "Individual unit in a list" , "Bit of news to broadcast" , "Separate article" , "Single unit" .)