The most common and most likely answer to this crossword clue is the 8 letter word THRASHES
I've seen this crossword clue in The Guardian
T
H
R
A
S
H
E
S
More clues leading to the result THRASHES
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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 THRASHES mean?
THRASHES noun- A beat or blow; the sound of beating.
- Thrash metal
- To beat mercilessly.
- To defeat utterly.
- To thresh.
- To move about wildly or violently; to flail; to labour.
- To extensively test a software system, giving a program various inputs and observing the behavior and outputs that result.
- In computer architecture, to cause poor performance of a virtual memory (or paging) system.