Heads of traditional eatery assembled meal (3)
I believe the answer is:
tea
'meal' is the definition.
(tea is a type of meal)
'heads of traditional eatery assembled' is the wordplay.
'heads of' says to take the initial letters.
The first letters of 'traditional eatery assembled' is 'TEA'.
(Other definitions for tea that I've seen before include "US party" , "Strangely, one may eat this drink" , "Plantation product" , "Food" , "Refresher course" .)