1Any of various freshwater prosobranch molluscs constituting the family Ampullariidae; especially those of the New World genus Pomacea, which are popular in tropical aquaria and can grow to a large size, but have become a serious pest following introduction in Asia.
2British the edible snail, Helix pomatia.
Origin
Late 18th century.
Definition of apple snail in US English:
apple snail
noun
1Any of various freshwater prosobranch molluscs constituting the family Ampullariidae; especially those of the New World genus Pomacea, which are popular in tropical aquaria and can grow to a large size, but have become a serious pest following introduction in Asia.