The most common and most likely answer to this crossword clue is the 10 letter word BARRACKING
I've seen this crossword clue in The Guardian
B
A
R
R
A
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More clues leading to the result BARRACKING
Buddy explains!

The straight part
We know that "boos and hisses" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case boos and hisses = barracking.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 BARRACKING mean?
BARRACKING verb- To house military personnel; to quarter.
- To live in barracks.
- To jeer and heckle; to attempt to disconcert by verbal means.
- To cheer for or support a team.
- An act of jeering or heckling.
- The act of cheering for or supporting a team.