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

Etymology

Origin of hemisphere

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

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

"We are synchronizing efforts to protect our hemisphere from transnational and regional threats by bringing Peru, now a major non-NATO ally, into the Shield of the Americas," Rubio said.

From Barron's ● Sep. 9, 2026

“Warmer-than-usual weather over the northern hemisphere winter could limit heating-related demand and help relieve upward pressure on natural gas and LNG prices in Europe and Asia,” says David Oxley, chief commodities economist.

From The Wall Street Journal ● Sep. 3, 2026

Scientists have detected unusual magnetic signatures in iron-rich minerals in the southern hemisphere.

From Science Daily ● Aug. 30, 2026

Average worldwide sea temperatures tend to reach their yearly peak in March or April, which corresponds to the end of summer in the southern hemisphere - and not in August.

From BBC ● Aug. 24, 2026

Throughout the hemisphere ecosystems cracked and heaved like winter ice.

From "1491" by Charles C. Mann

Together, the two observing sites greatly expand the geographic reach of the survey and allow SDSS-V to examine the sky from both hemispheres.

From Science Daily ● Aug. 14, 2026

They are also not unique to Europe but occur in both hemispheres across the world's middle latitudes.

From Barron's ● Jun. 23, 2026

The challenge of bringing a new piece of writing to life on the stage appeals to both hemispheres of his brain, the analytic and the intuitive sides.

From Los Angeles Times ● Apr. 8, 2026

Their analysis showed that pterosaurs had moderately enlarged brain hemispheres, a feature comparable to other dinosaur groups.

From Science Daily ● Dec. 9, 2025

A continuous dialogue is going on between the two hemispheres, channeled through an immense bundle of nerves, the corpus callosum, the bridge between creativity and analysis, both of which are necessary to understand the world.

From "Cosmos" by Carl Sagan

Related Words

• fraction