The most common and most likely answer to this crossword clue is the 12 letter word PAINTBRUSHES
P
A
I
N
T
B
R
U
S
H
E
S
More clues leading to the result PAINTBRUSHES
Buddy explains!

The straight part
We know that "ones bearing bristles" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case ones bearing bristles = paintbrushes.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 PAINTBRUSHES mean?
PAINTBRUSHES noun- A thin brush for applying paint.