n. A Greek geometer of the 3d century b. c.; also, his treatise on geometry, and hence, the principles of geometry, in general. [ 1913 Webster ]

n. Related to Euclid, or to the geometry of Euclid. [ 1913 Webster ]

Euclidian space (Geom.), the kind of space to which the axioms and definitions of Euclid, relative to straight lines and parallel lines, apply; -- called also flat space, and homaloidal space. [ 1913 Webster ]