In the end, even shorter (3)
I believe the answer is:
een
'shorter' is the definition.
I know nothing about this answer so I can't judge whether this works.
'in the end even' is the wordplay.
'in' indicates a hidden word.
'EEN' is hidden in the letters of 'the end even'.
Can you help me to learn more?
(Other definitions for een that I've seen before include "Even to the poet" , "Poetic form of even" , "Literary form of even" , "Even, poetically" .)