Friend featured in pop album (3)
I believe the answer is:
pal
'friend' is the definition.
(pal can mean a friend)
'featured in pop album' is the wordplay.
'featured in' says the answer is hidden in the clue.
'PAL' is hidden in the letters of 'pop album'.
(Other definitions for pal that I've seen before include "Brother" , "Friend (colloq.)" , "Crony" , "China" , "Mate, informal friend" .)