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

By applying deep learning models trained on tens of thousands of MRI scans, the team estimated the "brain age" of different regions in each hemisphere and examined how stroke affects both structure and recovery.

From Science Daily • Mar. 29, 2026

The US State Department has called it a threat to regional security in what it calls "our hemisphere."

From Barron's • Mar. 12, 2026

In this scenario, the U.S. has more influence in its hemisphere and in strategic geographies, from the Middle East to the Arctic.

From MarketWatch • Mar. 10, 2026

Then the senator turned his attention back to the Western hemisphere.

From Salon • Mar. 10, 2026

In February 1832, still “squeamish and uncomfortable,” Darwin crossed over to the southern hemisphere.

From "The Gene" by Siddhartha Mukherjee

Related Words

• fraction