twilight zone

American  

noun

1. the lowest level of the ocean that light can reach.

2. an ill-defined area between two distinct conditions, categories, etc., usually comprising certain features of both; an indefinite boundary.

   a twilight zone between fantasy and reality.

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twilight zone British  

noun

1. any indefinite or transitional condition or area

2. an area of a city or town, usually surrounding the central business district, where houses have become dilapidated

3. the lowest level of the ocean to which light can penetrate

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Etymology

Origin of twilight zone

First recorded in 1905–10

Example Sentences

See Examples For:

twilight zone

“An officer could simply invent an accusation of criminality, leaving the green-card holder trapped in a bureaucratic twilight zone for years before they have a chance to rebut the accusation at a hearing,” Mark writes.

From Slate ● Jun. 25, 2026

"It almost felt like being in the twilight zone," he added.

From BBC ● Feb. 23, 2026

Some companies have proposed releasing this waste within the twilight zone, but the environmental consequences of such practices have remained largely unknown -- until now.

From Science Daily ● Nov. 8, 2025

The deep sea begins at about 200 meters below sea level, where light starts to diminish in a region called the twilight zone.

From Salon ● May 21, 2025

Mr. Dunwoody uses the kiln as a cupboard, and the darkroom’s a twilight zone only Art Club members get to see.

From "Black Swan Green" by David Mitchell