Black snow leopard in spring (6)
I believe the answer is:
bounce
'spring' is the definition.
(bouncing is a kind of springing)
'black snow leopard' is the wordplay.
'black' becomes 'b' (as in pencil classifications).
'snow leopard' becomes 'ounce' ('ounce' can be a synonym of 'snow leopard').
'b'+'ounce'='BOUNCE'
'in' is the link.
(Other definitions for bounce that I've seen before include "Springiness" , "What a cheque may do if there are insufficient funds" , "Move energetically; rebound" , "Hop like rubber ball" , "Recoil like rubber ball" .)