Old English þreat "crowd, troop," also "oppression, menace," related to þreotan "to trouble, weary," from Proto-Germanic *threutanan (cf. German verdrießen "to vex"), from PIE *trud- "push, press" (cf. Latin trudere "to press, thrust," Old Church Slavonic trudu "oppression," Middle Irish trott "quarrel, conflict," M.Welsh cythrud "torture, torment, afflict"). Sense of "conditional declaration of hostile intention" was in Old English.