Word Study
hypotenuse
CIDE DICTIONARY
hypotenuse, n. [L. hypotenusa, Gr. , prob., subtending (sc. ), fr. to stretch under, subtend; under + to stretch. See Subtend.].
The side of a right-angled triangle that is opposite to the right angle. [1913 Webster]
OXFORD DICTIONARY
hypotenuse, n. the side opposite the right angle of a right-angled triangle.
Etymology
L hypotenusa f. Gk hupoteinousa (gramme) subtending (line) fem. part. of hupoteino (as HYPO-, teino stretch)
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