Remove during jousting (4)
I believe the answer is:
oust
'remove' is the definition.
(I know that oust is a more specific form of remove)
'during jousting' is the wordplay.
'during' indicates a hidden word.
'OUST' is hidden within 'jousting'.
(Other definitions for oust that I've seen before include "Overthrow" , "Extract" , "Send packing" , "Expel (from a place)" , "Get rid of" .)