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  

/ 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

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

However, for those in the northern hemisphere, it is generally recognised as the midsummer date with the longest amount of daylight and the shortest period of darkness.

From BBC • Jun. 16, 2026

“We have demand picking up in the northern hemisphere globally and so far we’re not really seeing much dent in demand,” says Tracy Shuchart of NinjaTrader Group.

From The Wall Street Journal • Jun. 9, 2026

"Naval Station Guantanamo Bay is a vital operational and logistical hub that supports US military efforts to counter threats that undermine security, stability and democracy in our hemisphere," US Southern Command said.

From Barron's • May 30, 2026

Shortages of rubber and chemical components have already been reported in Asia, and a prolonged war could affect grain prices when the northern hemisphere has to purchase fertilizers.

From MarketWatch • Apr. 29, 2026

Most of the time during the day the little ones drove her crazy; she couldn’t stand to be in the same hemisphere with them.

From "Maniac Magee" by Jerry Spinelli

Related Words

• fraction