The most common and most likely answer to this crossword clue is the 5 plus 4 letter word LIGHT MEAL
I've seen this crossword clue in The Guardian
L
I
G
H
T
M
E
A
L
More clues leading to the result LIGHT MEAL
Buddy explains!

The straight part
We know that "supper, perhaps" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case supper, perhaps = light meal.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.