First part of dinner is hot soup, perhaps (4)
I believe the answer is:
dish
'soup perhaps' is the definition.
(soup is a kind of dish)
'first part of dinner is hot' is the wordplay.
'first part of' suggests taking the first letters.
'hot' becomes 'h' (abbreviation eg on taps).
The first letter of 'dinner' is 'd'.
'd'+'is'+'h'='DISH'
(Other definitions for dish that I've seen before include "Receptacle" , "something in the oven?" , "What's presented on salver" , "course" , "Recipe; kitchen item" .)