Fruit and mat packed as well (6)
I believe the answer is:
tomato
'fruit' is the definition.
(type of fruit)
'mat packed as well' is the wordplay.
'packed' means one lot of letters goes inside another (some letters are packed into others).
'as well' becomes 'too' (both can mean 'also').
'mat' going inside 'too' is 'TOMATO'.
'and' acts as a link.
(Other definitions for tomato that I've seen before include "Shiny red fruit" , "Love apple (archaic)" , "A glossy red fruit eaten as a vegetable" , "Love apple (or "beef" fruit?)" , "A motto turned out to be fruit/veg" .)