The most common and most likely answer to this crossword clue is the 7 letter word CATTIER
I've seen this crossword clue in The Daily Telegraph
C
A
T
T
I
E
R
Buddy explains!

The straight part
We know that "Meaner" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case meaner = cattier.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 CATTIER mean?
CATTIER adjective- (of a person or remark) With subtle hostility in an effort to hurt, annoy or upset, particularly among women.
- Resembling or characteristic of a cat.