The most common and most likely answer to this crossword clue is the 8 letter word GRUNTERS
I've seen this crossword clue in The Times
G
R
U
N
T
E
R
S
Buddy explains!
The straight part
We know that "noisy swine!" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case noisy swine! = grunters.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 GRUNTERS mean?
GRUNTERS noun- One who grunts.
- Any of a group of fish of the family Terapontidae, which make a grunting sound when caught.
- A pig.
- (brass founding) A hook used in lifting a crucible.