Full of substance (5)
I believe the answer is:
meaty
'full of substance' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for meaty that I've seen before include "Brawny; full of substance" , "Full of substance, nourishment" , "Substantive -- like beef or pork?" , "Full of substance, flesh" , "Substantial, solid" .)