The most common and most likely answer to this crossword clue is the 5 letter word HARPY
I've seen this crossword clue in Independent
H
A
R
P
Y
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The straight part
We know that "Nasty woman" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case nasty woman = harpy.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 HARPY mean?
HARPY noun- A fabulous winged monster, ravenous and filthy, having the face of a woman and the body of a vulture.
- A shrewish woman.
- One who is rapacious or ravenous; an extortioner.
- The European moor buzzard or marsh harrier (Circus aeruginosus).
- A large and powerful double-crested, short-winged American eagle (Harpia harpyja).