Pronunciation: (boun'du-rē, -drē),[key] —n., —pl.-ries. 1. something that indicates bounds or limits; a limiting or bounding line.
2. Also called frontier.Math.the collection of all points of a given set having the property that every neighborhood of each point contains points in the set and in the complement of the set.
3. Cricket.a hit in which the ball reaches or crosses the boundary line of the field on one or more bounces, counting four runs for the batsman. Cf. six (def. 5).