Full of pith, yet not vegetable (5)
I believe the answer is:
meaty
'full' is the definition.
(thesaurus)
'pith yet not vegetable' is the wordplay.
I cannot quite see how this works, but
'pith' could be 'meat' ('meat' can be a synonym of 'pith') and 'meat' is found within the answer.
A single letter 'y' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...
'of' acts as a link.
Can you help me to learn more?
(Other definitions for meaty that I've seen before include "Fleshy, or full of informative matter" , "Beefy" , "Fleshy - satisfying" , "Substantial, solid" , "Brawny; full of substance" .)