- hypotenuse
- hypotenuse: [16] The hypotenuse is etymologically a line that is ‘stretched under’ the right angle of a triangle. The word comes via Latin hypotēnūsa from Greek hupoteínousa, a derivative of hupoteínein. This was a compound verb formed from the prefix hupo- ‘under’ and teínein ‘stretch’ (a relative of English tend, tense, etc).
=> tend, tense - hypotenuse (n.)
- 1570s, from Late Latin hypotenusa, from Greek hypoteinousa "stretching under" (the right angle), fem. present participle of hypoteinein, from hypo- "under" (see sub-) + teinein "to stretch" (see tenet). Formerly often erroneously hypothenuse.