The most common and most likely answer to this crossword clue is the 5 letter word SNUBS
I've seen this crossword clue in Independent
S
N
U
B
S
More clues leading to the result SNUBS
Buddy explains!

The straight part
We know that "Insults" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case insults = snubs.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 SNUBS mean?
SNUBS noun- A deliberate affront or slight.
- A sudden checking of a cable or rope.
- A knot; a protuberance; a snag.
- To slight, ignore or behave coldly toward someone.
- To turn down; to dismiss.
- To check; to reprimand.
- To stub out (a cigarette etc).
- To halt the movement of a rope etc by turning it about a cleat or bollard etc; to secure a vessel in this manner.
- To clip or break off the end of; to check or stunt the growth of.
- To sob with convulsions.