The most common and most likely answer to this crossword clue is the 7 letter word LASSIES
I've seen this crossword clue in The Guardian
L
A
S
S
I
E
S
More clues leading to the result LASSIES
Buddy explains!

The straight part
We know that "girls" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case girls = lassies.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 LASSIES mean?
LASSIES noun- A young girl, a lass, especially one seen as a sweetheart.