Word Origin & History
tenet"principle," properly "a thing held (to be true)," 1413, from L. tenet "he holds," third person singular present indicative of tenere "to hold, to keep, to maintain" from PIE base *ten- "to stretch" (cf. Skt. tantram "loom," tanoti "stretches, lasts;" Pers. tar "string;" Lith. tankus "compact," i.e.
"tightened;" Gk. teinein "to stretch," tasis "a stretching, tension," tenos "sinew," tetanos "stiff, rigid," tonos "string," hence "sound, pitch;" L. tendere "to stretch," tenuis "thin, rare, fine;" O.C.S. tento "cord;" O.E. thynne "thin"). Connection notion between "stretch" and "hold" is "to cause to maintain." The modern sense is probably because tenet was used in M.L. to introduce a statement of doctrine.