Fruit preserve (3)
'fruit preserve' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for jam that I've seen before include "Fruit preserve" , "Preserve; pack tightly" , "Sweet stuff for bread - stuff it in" , "Conserve" , "awful traffic" .)
(Other definitions for marmalade that I've seen before include "Orange preserve" , "Jame made from citrus fruits" , "Eleven's [PRESERVE]" , "Kind of cat" , "group?" .)