hemisphere

American  

[hem-i-sfeer] / ˈhɛm ɪˌsfɪər /

noun

1. (often initial capital letter) half of the terrestrial globe or celestial sphere, especially one of the halves into which the earth is divided.

2. a map or projection representing one of these halves.

3. a half of a sphere.

4. Anatomy. either of the lateral halves of the cerebrum or cerebellum.

5. the area within which something occurs or dominates; sphere; realm.

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hemisphere British  

/ ˌhɛmɪˈsfɛrɪk, ˈhɛmɪˌsfɪə /

noun

1. one half of a sphere

2. 1. half of the terrestrial globe, divided into northern and southern hemispheres by the equator or into eastern and western hemispheres by some meridians, usually 0° and 180°

   2. a map or projection of one of the hemispheres

3. either of the two halves of the celestial sphere that lie north or south of the celestial equator

4. anatomy short for cerebral hemisphere

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hemisphere Scientific  

/ hĕm′ĭ-sfîr′ /

1. One half of a sphere, formed by a plane that passes through the center of the sphere.

2. Either the northern or southern half of the Earth as divided by the equator, or the eastern or western half as divided by a meridian, especially the prime meridian.

3. One half of the celestial sphere as divided by any of various great circles, especially the celestial equator and the ecliptic.

4. See more at celestial sphere

5. See cerebral hemisphere

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hemisphere Cultural  

1. Any half of the Earth's surface.

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Other Word Forms

• hemispheric adjective

Etymology

Origin of hemisphere

1325–75; < Latin hēmisphaerium < Greek hēmisphaírion; replacing Middle English emysperie < Old French emispere < Latin

Example Sentences

Even so, the simplest explanation based on current evidence points to a large volcanic eruption in the northern hemisphere as the main driver of the Younger Dryas.

From Science Daily • Mar. 20, 2026

With the northern hemisphere only exiting official winter on Friday -- the first day of astronomical spring -- the soaring temperatures were wreaking havoc on wildlife in the West.

From Barron's • Mar. 20, 2026

Poorer countries devote a bigger part of their incomes to essentials like food and transport than the Western hemisphere.

From MarketWatch • Mar. 20, 2026

They can't be held in the northern hemisphere summer because it would be too hot in Bahrain and Saudi Arabia.

From BBC • Mar. 10, 2026

From the highest vantage point you can make out only the brain’s two big hemispheres, so I began with studies of split-brain patients and other discoveries that locate language in the left hemisphere.

From "The Sense of Style" by Steven Pinker

Related Words

• fraction