- isosceles (adj.)
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- "having two equal sides," 1550s, from Late Latin isosceles, from Greek isoskeles "with equal legs; isosceles; that can be divided into two equal parts," from isos "equal, identical" (see iso-) + skelos "leg," from PIE *skel-es-, from root *(s)kel- (3) "crooked" (see scoliosis).