The most common and most likely answer to this crossword clue is the 9 letter word BACKSWEPT
I've seen this crossword clue in The Times
B
A
C
K
S
W
E
P
T
More clues leading to the result BACKSWEPT
Buddy explains!
The straight part
We know that "sloping off to the rear" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sloping off to the rear = backswept.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 BACKSWEPT mean?
BACKSWEPT adjective- Swept back.