ellipsoid vs roundabout

ellipsoid

adj
  • Of or pertaining to an ellipse; elliptic. 

  • Shaped like an ellipse; elliptical. 

  • Having the tridimensional shape of an ellipse rotated on its long axis. 

noun
  • A surface, all of whose cross sections are elliptic or circular (including the sphere), that generalises the ellipse and in Cartesian coordinates (x, y, z) is a quadric with equation x²/a² + y²/b² + z²/c² = 1. 

  • Such a surface used as a model of the shape of the earth. 

roundabout

adj
  • Encircling; enveloping; comprehensive. 

  • Indirect, circuitous, or circumlocutionary. 

noun
  • A horizontal wheel which rotates around a central axis when pushed and on which children ride, often found in parks as a children's play apparatus. 

  • A fairground carousel. 

  • A detour. 

  • A short, close-fitting coat or jacket worn by men or boys, especially in the 19th century. 

  • A road junction at which traffic streams circularly around a central island. 

verb
  • To play on a roundabout (carousel) 

  • To travel round roundabouts 

  • To talk in a roundabout, indirect manner 

How often have the words ellipsoid and roundabout occurred in a corpus of books? (source: Google Ngram Viewer )