Online Google Dictionary

contractibility 中文解釋 wordnet sense Collocation Usage Collins Definition
  1. (Contractible) In mathematics, a topological space X is contractible if the identity map on X is null-homotopic, i.e. if it is homotopic to some constant map. Intuitively, a contractible space is one that can be continuously shrunk to a point.
  2. (contractible) Capable of contraction; (of a topological set) Able to be reduced to one of its points by a continuous deformation