The most common and most likely answer to this crossword clue is the 8 plus 6 letter word INVERTED COMMAS
I've seen this crossword clue in The Times
I
N
V
E
R
T
E
D
C
O
M
M
A
S
More clues leading to the result INVERTED COMMAS
Buddy explains!

The straight part
We know that "Quotes" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case quotes = inverted commas.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.