An end-of-term mark to handicap one seriously (4)
I believe the answer is:
maim
'handicap one seriously' is the definition.
I can't judge whether this definition defines the answer.
'an end-of-term mark' is the wordplay.
'an end of' says to take the final letters.
'mark' becomes 'aim' ().
The final letter of 'term' is 'm'.
'm'+'aim'='MAIM'
'to' acts as a link.
Can you help me to learn more?
(Other definitions for maim that I've seen before include "Wound and permanently disfigure" , "Wound and cripple" , "Wound so that part of body is permanently damaged" , "Wound or injure, disable" , "Injure and cripple" .)