Sausage in a roll (3,3)
'sausage in a roll' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for hot dog that I've seen before include "Meat in roll" , "Sausage in a bap" , "Sausage sandwich - acrobatic skier" , "Sausage in breae roll" , "Frankfurter in a roll" .)
(Other definitions for hotdog that I've seen before include "Food served at arena" , "junk food" , "snack" .)