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

The goal is to better understand groundwater beneath the Great Salt Lake, the largest terminal lake in the Western Hemisphere.

From Science Daily • Mar. 21, 2026

Rather than being demeaned, Rubio was performing his role as Secretary of State by addressing a coalition of Western Hemisphere countries assembled at an official government summit focused on regional cooperation and counternarcotics efforts.

From Los Angeles Times • Mar. 9, 2026

Within the asset class, investors are balancing tech-forward Asian markets with a tech-laggard Western Hemisphere, adds Malcolm Dorson, head of emerging markets strategy at Global X exchange-traded funds.

From Barron's • Feb. 12, 2026

"What defines an America First policy is something that is in the direct interest of the American citizenry," said Joshua Trevino, a senior fellow for the Western Hemisphere Initiative at the America First Policy Institute.

From BBC • Feb. 8, 2026

Laboratory tests showed that the bones could be fifteen thousand years old—possibly the oldest human remains in the Western Hemisphere.

From "1491" by Charles C. Mann