Like illustration, something set on dining table (5)
I believe the answer is:
aspic
'something set on dining table' is the definition.
'like illustration' is the wordplay.
'like' becomes 'as'.
'illustration' becomes 'pic' (short for picture).
'as'+'pic'='ASPIC'
(Other definitions for aspic that I've seen before include "Glaze" , "garnish" , "Savoury jelly for meat or vegetable" , "Lavender" , "that's clear?" .)