The most common and most likely answer to this crossword clue is the 10 letter word BELITTLING
I've seen this crossword clue in Financial Times
B
E
L
I
T
T
L
I
N
G
Buddy explains!

The straight part
We know that "being scornful" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case being scornful = belittling.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 BELITTLING mean?
BELITTLING verb- To knowingly say that something is smaller or less important than it actually is, especially as a way of showing contempt or deprecation.
- Belittlement