Definition of soursop:
(n) :
The tart, spiny, yellow-green fruit of this tree.
(n) :
A small tropical evergreen tree, Annona muricata.
(n) :
Bermuda buttercup (Oxalis pes-caprae), an edible wood sorrel native to South Africa
(n) :
(by extension) any wood sorrel, especially when used as food