title: Osculate
text: # Osculate
  
  In mathematics, osculate, meaning to touch (from the Latin osculum meaning kiss), may refer to:
  
  * osculant, an invariant of hypersurfaces
  * osculating circle
  * osculating curve
  * osculating plane
  * osculating orbit
  * osculating sphere
  
  The obsolete Quinarian system of biological classification attempted to group creatures into circles which could touch or overlap with adjacent circles, a phenomenon called 'osculation'.
  
  