The most common and most likely answer to this crossword clue is the 6 letter word HOYDEN
I've seen this crossword clue in The Times
H
O
Y
D
E
N
Buddy explains!

The straight part
We know that "Spirited girl’" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case spirited girl’ = hoyden.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 HOYDEN mean?
HOYDEN noun- A rude, uncultured or rowdy girl or woman.
- To behave in a hoydenish manner.
- Like a hoyden: high-spirited and boisterous; saucy, tomboyish.