Wait on guests eating meat (6)
I believe the answer is:
tongue
'meat' is the definition.
(tongue is a kind of meat)
'wait on guests eating' is the wordplay.
'eating' indicates the answer is hidden within the clue.
'TONGUE' is hidden in the letters of 'wait on guests'.
(Other definitions for tongue that I've seen before include "Language; promontory" , "Muscular organ inthe mouth" , "One gut in the mouth" , "Mouth organ; language" , "Part of body - language!" .)