Wrinkled tangelo (4)
I believe the answer is:
ugli
'wrinkled tangelo' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for ugli that I've seen before include "Tropical fruit" , "West Indian citrus fruit" , "Unappealing-sounding fruit?" , "Citrus fruit of the West Indies" , "Orange-grapefruit cross" .)