Vegan's no-no
I believe the answer is:
meat
'vegan's no-no' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for meat that I've seen before include "Chops, steaks etc" , "Flesh for eating" , "Ham, pork, chicken etc" , "Food for carnivores" , "The flesh of animals as food" .)