hemisphere

American  

[hem-i-sfeer] / ˈhɛm ɪˌsfɪər /

noun

• hemispheres
  plural

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  

/ 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

Derived Forms

• hemispheric
  adjective

Inflected Forms

Nouns

• hemispheres
  plural

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Etymology

Origin of hemisphere

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

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Explanation

A hemisphere is half of a sphere. If it’s a cold winter in the northern hemisphere, take a winter getaway to sunbathe somewhere in the southern hemisphere. Hemisphere comes from the Greek, and combines the prefix hemi-, for "half," with sphere, or "perfectly round ball." We talk about the earth as divided at the equator into the northern and southern hemispheres (or divided at the prime meridian into eastern and western hemispheres). In biology, there are two cerebral, or brain, hemispheres — also known as the right and left sides of the brain.

Example Sentences

See Examples For:

hemisphere hemispheres

However, the measurements showed that this darker hemisphere was not warm enough to explain all the missing heat.

From Science Daily ● Oct. 27, 2026

He takes up his role as Port Lockroy postmaster from late October to March, during the southern hemisphere summer.

From BBC ● Oct. 25, 2026

The distortion occurs on the planet's "evening" side, where powerful atmospheric winds carry heat away from the hemisphere that permanently faces its star and toward the hemisphere locked in darkness.

From Science Daily ● Oct. 16, 2026

With Australia's fire services warning that the start of the northern hemisphere summer later this year could see more intense blazes, Oaka's training will be fast-tracked.

From Barron's ● Sep. 30, 2026

Homo sapiens was the first and only human species to reach the western hemisphere landmass, arriving about 16,000 years ago, that is in or around 14,000 BC.

From "Sapiens: A Brief History of Humankind" by Yuval Noah Harari

The observations provide valuable information about WASP-17b's atmospheric chemistry and temperature variations, including differences between its equator and poles and between its permanently illuminated and dark hemispheres.

From Science Daily ● Oct. 16, 2026

"Our findings suggest that the mass of Earth's water and air moving between the hemispheres is smaller than previously thought."

From Science Daily ● Oct. 7, 2026

Mars has long been known to look very different across its two hemispheres.

From Science Daily ● Aug. 30, 2026

Without material from the far side, they could not directly test whether solar wind implantation differed systematically between the two hemispheres.

From Science Daily ● Jul. 21, 2026

The two hemispheres specialize in different mental skills, but brain functions are not as neatly divided as they appear.

From "Phineas Gage" by John Fleischman

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