Spirited opening of performance, promising (6)
I believe the answer is:
plucky
'spirited' is the definition.
(similar in meaning)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for plucky that I've seen before include "Doughty" , "Game" , "Determined, courageous" , "Feisty, gutsy" , "with bottle" .)