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

U.S. officials wanted to ensure reliable access to crude in the Western Hemisphere in the face of instability in the Middle East.

From The Wall Street Journal • Mar. 15, 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

The latter document spotlights Washington’s intention to focus on the homeland and the Western Hemisphere.

From Barron's • Feb. 13, 2026

Beyond that, what was the population of the Western Hemisphere in 1491?

From "1491" by Charles C. Mann