Show insect behind leaf (7)
I believe the answer is:
pageant
'show' is the definition.
(a show or display)
'insect behind leaf' is the wordplay.
'insect' becomes 'ant' (ant is a kind of insect).
'behind' is a charade indicator (letters next to each other).
'leaf' becomes 'page' (page is a kind of leaf).
'ant' put after 'page' is 'PAGEANT'.
(Other definitions for pageant that I've seen before include "Neat gap for colourful spectacle" , "Tableaux or dramatic scenes depicting historical events" , "Show" , "Dramatic performance" , "Extravagant dramatic display" .)