The most common and most likely answer to this crossword clue is the 4 letter word YAKS
Y
A
K
S
More clues leading to the result YAKS
Buddy explains!

The straight part
We know that "Hairy beasts/jaws" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case hairy beasts/jaws = yaks.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 YAKS mean?
YAKS noun- An ox-like mammal native to the Himalayas, Mongolia, Burma, and Tibet with dark, long, and silky hair, a horse-like tail, and a full, bushy mane.
- A talk, particular an informal talk; chattering; gossip.
- A laugh.
- Vomit.
- A kayak.