Pronunciation: (tu-pol'u-jē), [key]
—pl. -gies for 3. Math.
1. the study of those properties of geometric forms that remain invariant under certain transformations, as bending or stretching.
2. Also called point set topology. the study of limits in sets considered as collections of points.
3. a collection of open sets making a given set a topological space.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.