The most common and most likely answer to this crossword clue is the 7 letter word CORSETS
I've seen this crossword clue in Financial Times
C
O
R
S
E
T
S
More clues leading to the result CORSETS
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The straight part
We know that "stays" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case stays = corsets.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 CORSETS mean?
CORSETS noun- A woman's foundation garment, reinforced with stays, that supports the waistline, hips and bust.
- A tight-fitting gown or basque worn by both men and women during the Middle Ages.
- A regulation that limited the growth of British banks' interest-bearing deposits.
- To enclose in a corset; to wear a corset.
- To restrict or confine.