tension Look up tension at Dictionary.com
1533, "a stretched condition," from M.Fr. tension, from L. tensionem (nom. tensio) "a stretching" (in M.L. "a struggle, contest"), from tensus, pp. of tendere "to stretch," from PIE base *ten- "stretch" (see tenet). The sense of "nervous strain" is first recorded 1763. The meaning "electromotive force" (in high-tension wires) is recorded from 1802.