Swallow meat regularly for disciplinarian (8)
I believe the answer is:
martinet
'for disciplinarian' is the definition.
(synonyms)
'swallow meat regularly' is the wordplay.
'swallow' becomes 'martin' (martin is a kind of swallow).
'regularly' means one should take alternating letters (regularly take one letter, leave next etc.).
The alternating letters of 'meat' are 'et'.
'martin'+'et'='MARTINET'
(Other definitions for martinet that I've seen before include "'Disciplinarian, exacts strict conformity to rules (8)'" , "Trite man becomes a tyrant" , "Person who demands strict obedience" , "Tyrant, one who demands strict obedience" , "Despot" .)