Provide with witty remark after end of lecture (5)
I believe the answer is:
equip
'provide with' is the definition.
(I've seen this before)
'witty remark after end of lecture' is the wordplay.
'witty remark' becomes 'quip' (I've seen this before).
'after' is a charade indicator (letters next to each other).
'end of' suggests the final letters.
The last letter of 'lecture' is 'e'.
'quip' put after 'e' is 'EQUIP'.
(Other definitions for equip that I've seen before include "Provide stuff" , "Furnish, fit out" , "Sally" , "Provide with suitable gear" , "Fit out, supply" .)