Threshold

From Old English Ã¾rescold ("doorsill", "point of entering"), from Ã¾rescan ("tread", "trample")

Full definition of threshold

(plural thresholds)

The bottom-most part of a doorway that one crosses to enter; a sill.
(by extension) An entrance
The start of the landing area of a runway
(engineering) The quantitative point at which an action is triggered, especially a lower limit
The wage or salary at which income tax becomes due
The outset of an action or project
The point where one mentally or physically is vulnerable in response to provocation or to particular things in general. As in emotions, stress, or pain.
The point of beginning or entryFrom all the pressure my partner has been through lately, his emotion threshold has suddenly gotten pretty low these days. I can tell because he easily loses it when he is around people or hears about anything to do with his concerns.