[thresh.old] n [ME thresshold, fr. OE threscwald; akin to ON threskjoldr threshold, OE threscan to thresh] (bef. 12c) 1: the plank, stone, or piece of timber that lies under a door: sill
2. a: gate, door b (1): end, boundary; specif: the end of a runway (2): the place or point of entering or beginning: outset "on the ~ of a new age" 3 a: the point at which a physiological or psychological effect begins to be produced b: a level, point, or value above which something is true or will take place and below which it is not or will not