The most common and most likely answer to this crossword clue is the 8 letter word JAUNTIER
I've seen this crossword clue in The Times
J
A
U
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T
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R
More clues leading to the result JAUNTIER
Buddy explains!

The straight part
We know that "More sprightly" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case more sprightly = jauntier.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 JAUNTIER mean?
JAUNTIER adjective- Airy; showy; finical.
- (by extension) Characterized by an affected or fantastical manner.
- Dapper or stylish.
- Ostentatiously self-confident.