The most common and most likely answer to this crossword clue is the 7 letter word MAIDENS
I've seen this crossword clue in The Guardian
M
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The straight part
We know that "young females /young females" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case young females /young females = maidens.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 MAIDENS mean?
MAIDENS noun- One of the triune goddesses of the Lady in Wicca alongside the Crone and Mother representing a girl or a young woman
- A girl or an unmarried young woman.
- A female virgin.
- A man with no experience of sex, especially because of deliberate abstention.
- A maidservant.
- A clothes maiden.
- An unmarried woman, especially an older woman.
- A racehorse without any victory, i.e. one having a "virgin record".
- A horse race in which all starters are maidens.
- A Scottish counterpart of the guillotine.
- A maiden over.
- A machine for washing linen.