The most common and most likely answer to this crossword clue is the 4 letter word CHOW
I've seen this crossword clue in The Guardian
C
H
O
W
Buddy explains!
The straight part
We know that "A dog/dinner" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case a dog/dinner = chow.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does CHOW mean?
CHOW noun- Food, especially snacks.
- A Chow Chow.
- A Chinese person.
- To eat.
- A prefecture or district of the second rank in China, or the chief city of such a district.
- A run of three consecutive tiles of the same suit.
- To call a discarded tile to produce a chow.