noun
threshold
A doorway sill, or the point at which an effect or response begins.
Where it comes from
Threshold ordinarily means a doorway sill, or the point at which an effect or response begins. Threshold descends from Old English forms such as threscwald. It has Germanic relatives, including Old Norse threskjoldr, and its first element is probably related to the verb thresh, but the compound's exact formation is unknown. The word named a boundary and a doorway sill long before science used it for the point where a stimulus begins to produce an effect.
How the meaning developed
The familiar story that the sill held threshing debris inside a house has no direct historical support.
Sources
Definitions adapted from Open English WordNet where applicable. License and attribution. Word-history text comes from Lexifour’s sourced social research; pages are assembled automatically, not individually fact-checked on every update.
Updated 2026-10-05. Report a correction.