The branch of pure mathematics that deals only with the properties of a figure X that hold for every figure into which X can be transformed with a one-to-one correspondence that is continuous in both directions WordNet 3.0 & Open English WordNet

In mathematics, topology is concerned with the properties of a geometric object that are preserved under continuous deformations, such as stretching, twisting, crumpling, and bending; that is, without closing holes, opening holes, tearing, gluing, or passing through itself. Wikipedia

Branch of mathematics concerned with geometric properties preserved under continuous deformation. Wikipedia Disambiguation

Branch of mathematics Wikidata

A branch of mathematics concerned with spatial properties preserved under bicontinuous deformation. OmegaWiki

A branch of mathematics studying those properties of a geometric figure or solid that are not changed by stretching, bending and similar homeomorphisms. Wiktionary