Substantial food for thought for Turkey and leader of Yemen (5)
I believe the answer is:
meaty
'substantial' is the definition.
(thesaurus)
'food for thought for turkey and leader of yemen' is the wordplay.
I cannot really see how this works, but
'food' could be 'meat' (meat is a kind of food) and 'meat' is found in the answer.
A single letter 'y' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for meaty that I've seen before include "Full of substance, flesh" , "Substantial, solid" , "Brawny; full of substance" , "Fleshy - satisfying" , "Fleshy, or full of informative matter" .)