Leader of academy donated a plant (5)
I believe the answer is:
agave
'a plant' is the definition.
(agave is a kind of plant)
'leader of academy donated' is the wordplay.
'leader of' says to take the initial letters.
'donated' becomes 'gave' (I've seen this before).
The initial letter of 'academy' is 'a'.
'a'+'gave'='AGAVE'
(Other definitions for agave that I've seen before include "Spiky succulent" , "native growing up in tropical America" , "Succulent; daughter of Cadmus" , "Succulent plant" , "plant in Mexico" .)