I. ˈthreshˌ(h)ōld noun
( -s )
Etymology: Middle English threshwold, thresshold, from Old English threscwald, threscold, akin to Old Norse threskjöldr threshold, Old English threscan, therscan to thresh
1. : the plank, stone, or piece of timber or metal that lies under a door ; especially : sill
2.
a. : gate , door
b.
(1) : end , boundary ; specifically : the end of a runway
(2) : the place or point of entering or beginning : entrance , outset
the threshold of an era of scientific and technological development — A.L.Nickerson
on the threshold of adulthood — Frances Keene
a hamlet on the threshold of a narrow valley — American Guide Series: Oregon
3.
[translation of German schwelle ]
: the point at which a physiological or psychological effect begins to be produced (as the degree of stimulation of a nerve or nerve center which just produces a response or the concentration of sugar in the blood at which sugar just begins to pass the barrier of the kidneys and enter the urine)
below the threshold of consciousness
the threshold of pain
a high renal clearance threshold
with an alteration of the physical environment some ecological thresholds of the ecosystem or of certain of its components may be crossed and the system disrupted — J.R.Beerbower
II. adjective
1. : resembling a threshold ; also : suggesting a threshold in nature, use, or function
2. : that constitutes a threshold
a threshold voltage
threshold levels of sugar