Visit a restaurant (3,3)
(Other definitions for dine out that I've seen before include "Eat away from home" , "Use a restaurant" , "Eat in a restaurant" .)
'visit a restaurant' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for eat out that I've seen before include "'Don't dine at home (3,3)'" , "Etch" , "Go to restaurant for meal, don't dine at home" , "Dine in restaurant rather than home" , "Dine away from home" .)