Spritely - that's the Spanish and French conclusion (5)
I believe the answer is:
elfin
'spritely' is the definition.
(I've seen this in another clue)
'the spanish and french conclusion' is the wordplay.
'the spanish' becomes 'el' ('the' in Spanish).
'and' is a charade indicator (letters next to each other).
'french conclusion' becomes 'fin' (I can't justify this - if you can you should believe this answer much more).
'el'+'fin'='ELFIN'
'that's' acts as a link.
Can you help me to learn more?
(Other definitions for elfin that I've seen before include "Resembling one of the little people" , "Spritely" , "Like a mischievous fairy" , "Pixie-like" , "puckish" .)