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Carlo Beenakker
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The suffix "-oid" means the same as "quasi", so "resembling", "like". A groupoid is a quasi-group, like a group.

From the "early use" database I find:

250 BC: conchoid
200 BC: cissoid
400: trapezoid
1650: trochoid
1672: ellipsoid
1685: cochleoid
1830: epicycloid
1836: paraboloid
1837: strophoid
1844: centroid
1872: geoid, gyroid
1878: nephroid
1879: deltoid
1881: prismatoid
1891: cuboid
1935: matroid

Carlo Beenakker
  • 188.2k
  • 18
  • 448
  • 651