Something found in youngster's yellowing underwear? (1-6)
I believe the answer is:
y-fronts
'underwear?' is the definition.
(type of underwear)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for y-fronts that I've seen before include "Men's underwear" , "Pants for men" , "Type of underpants" , "Men's pants" , "briefs" .)