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

However, studies have shown that higher latitudes, particularly in the northern hemisphere, will see the biggest increases in favourable conditions for storms to form, and those that do may be more violent.

From BBC ● Sep. 5, 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

Gravity measurements suggest that the interior beneath Mars's southern hemisphere is about 200 to 400 degrees Celsius warmer than the north and may be partially molten.

From Science Daily ● Aug. 30, 2026

Vega is the brightest star in the constellation Lyra, and the third brightest star in the northern hemisphere.

From "We Are the Ants" by Shaun David Hutchinson

To investigate this connection, the team studied a large multicenter group consisting of fifty patients and one hundred brain hemispheres.

From Science Daily ● Aug. 12, 2026

Krypton and xenon provided additional evidence that the two hemispheres were exposed to particles with different energies.

From Science Daily ● Jul. 21, 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

The biennial Nations Championship will feature leading teams from both the northern and southern hemispheres.

From Barron's ● Feb. 23, 2026

Inside the brain, you can see die different lobes of the cortex; the corpus callosum, which joins the two hemispheres; the cerebellum at the back of the head; and the brain stem.

From "Phineas Gage" by John Fleischman

Related Words

• fraction