The most common and most likely answer to this crossword clue is the 9 letter word OVERSIZED
I've seen this crossword clue in The Daily Telegraph
O
V
E
R
S
I
Z
E
D
Buddy explains!

The straight part
We know that "Larger than usual" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case larger than usual = oversized.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 OVERSIZED mean?
OVERSIZED adjective- Very large; especially of something larger than normal for its type.