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• Western Hemisphere
  Western Hemisphere

  noun

  the western part of the terrestrial globe, roughly extending from the prime meridian west to the antimeridian: sometimes considered synonymous with the New World because the Americas are its primary composition, the Western Hemisphere technically extends into western Eurasia and Africa, easternmost Siberia, and part of Antarctica as well.
• western hemisphere
  western hemisphere

  noun

  that half of the globe containing the Americas, lying to the west of the Greenwich or another meridian

Western Hemisphere

American  

[wes-tern hem-i-sfeer] / ˈwɛs tərn ˈhɛm ɪˌsfɪər /

noun

1. the western part of the terrestrial globe, roughly extending from the prime meridian west to the antimeridian: sometimes considered synonymous with the New World because the Americas are its primary composition, the Western Hemisphere technically extends into western Eurasia and Africa, easternmost Siberia, and part of Antarctica as well.

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western hemisphere British  

noun

1. that half of the globe containing the Americas, lying to the west of the Greenwich or another meridian

2. the lands contained in this, esp the Americas

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Western Hemisphere Scientific  

/ wĕs′tərn /

1. The half of the Earth that includes North America, Central America, and South America, as divided roughly by the 0° and 180° meridians.

2. See more at prime meridian

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Etymology

Origin of Western Hemisphere

First recorded in 1640–50

Example Sentences

In the short term, it will probably drive some countries back to burning coal and accelerate oil drilling in the Western Hemisphere.

From Salon • Jun. 21, 2026

Under a new centrist president, Rodrigo Paz, Bolivia has joined the Shield of the Americas, the US-led security initiative in the Western Hemisphere.

From BBC • Jun. 17, 2026

The Haitian Revolution may seem out of place in an exhibition celebrating the U.S., but Haiti was the second independent nation in the Western Hemisphere.

From Los Angeles Times • Jun. 10, 2026

And those troops have been unable to train or maintain their weapons, said Craig Deare, who served early in Trump’s first administration as senior director for Western Hemisphere affairs at the National Security Council.

From The Wall Street Journal • May 22, 2026

In fact, Haiti is the poorest country in the Western Hemisphere.

From "Mountains Beyond Mountains" by Tracy Kidder and Michael French