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noun thresh·old \ˈthresh-ˌhōld, ˈthre-ˌshōld\

Simple Definition of threshold

  • : a piece of wood, metal, or stone that forms the bottom of a door and that you walk over as you enter a room or building

  • : the point or level at which something begins or changes

Full Definition of threshold

  1. 1 :  the plank, stone, or piece of timber that lies under a door :  sill

  2. 2a :  gate, doorb (1) :  end, boundary; specifically :  the end of a runway (2) :  the place or point of entering or beginning :  outset <on the threshold of a new age>

  3. 3a :  the point at which a physiological or psychological effect begins to be produced <has a high threshold for pain>b :  a level, point, or value above which something is true or will take place and below which it is not or will not

Examples of threshold

  1. … we still hadn't grasped that we had crossed a threshold where it no longer mattered what passport you carried, that you were young and loved, … or that you were a noncombatant. —Paul Salopek, National Geographic, April 2008

  2. As we speak, the very worst of humanity is on the threshold of acquiring the most powerful weapons in history—this is a fear and a consideration to be taken very seriously. —Charles Krauthammer, New Republic, 29 Apr. 2002

  3. We thought that we were on the threshold of an age of space travel. But the greatest impact of the trip to the moon was on how we view the Earth. —Suzannah Lessard, Wilson Quarterly, Summer 2001

  4. He stepped across the threshold.

  5. If your income rises above a certain threshold, your tax rate also rises.

Origin of threshold

Middle English thresshold, from Old English threscwald; akin to Old Norse threskjǫldr threshold, Old English threscan to thresh

First Known Use: before 12th century

Other Building Terms

THRESHOLD Defined for Kids


noun thresh·old \ˈthresh-ˌhōld\

Definition of threshold

  1. 1 :  the sill of a door

  2. 2 :  a point or place of beginning or entering <Ralph had a scary feeling he was on the threshold of adventure. — Beverly Cleary, The Mouse and the Motorcycle>

Medical Dictionary


noun thresh·old \ˈthresh-ˌ(h)ōld\

Medical Definition of threshold

  1. :  the point at which a physiological or psychological effect begins to be produced (as the degree of stimulation of a nerve 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>—called also limen

Seen and Heard

What made you want to look up threshold? Please tell us where you read or heard it (including the quote, if possible).


February 13, 2016

a trying or distressing experience

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