Word Study
isosceles
CIDE DICTIONARY
isosceles, a. [L., fr. Gr. ; 'i`sos equal + leg.].
Having two legs or sides that are equal; -- said of a triangle. [1913 Webster]
OXFORD DICTIONARY
isosceles, adj. (of a triangle) having two sides equal.
Etymology
LL f. Gk isoskeles (as ISO-, skelos leg)
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