The most common and most likely answer to this crossword clue is the 11 letter word MUTTONCHOPS
I've seen this crossword clue in The Times
M
U
T
T
O
N
C
H
O
P
S
Buddy explains!

The straight part
We know that "Face hairs" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case face hairs = muttonchops.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 MUTTONCHOPS mean?
MUTTONCHOPS noun- A cut of sheep's meat, often containing a section of a rib.
- (by extension) A facial hairstyle consisting of sideburns and a moustache without a beard.