n. 1. A piece of wood or stone placed beneath a door; a doorsill. 2. Either end of an airport runway. 3. The place or point of beginning; the outset: on the threshold of a new era. 4. The point that must be exceeded to begin producing a given effect or result or to elicit a response: a low threshold of pain. [Middle English thresshold, from Old English therscold, threscold; see terə-1 in the Appendix of Indo-European roots.] |
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