An Etymological Dictionary of Astronomy and Astrophysics

In a → right triangle, the side opposite to the right angle.

Etymology (EN): L.L. hypotenusa, from Gk. hypoteinousa “stretching under” (the right angle), from hypoteinein, from → hypo- “under” + teinein “to stretch,” → tension.

Etymology (PE): Vatar loan from Ar.