Proliferate in one great leap? (6)
I believe the answer is:
abound
'proliferate' is the definition.
(thesaurus)
'one great leap?' is the wordplay.
'one great' becomes 'a' (I can't justify this - if you can you should give a lot more credence to this answer).
'leap?' becomes 'bound' ('bound' can be a synonym of 'leap').
'a'+'bound'='ABOUND'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for abound that I've seen before include "Be plentiful, swarm" , "Be plentiful, say fish in river" , "Be widely available" , "Be plentiful, be present on great quantities" , "Exist in large quantities" .)