hemisphere

noun
hemi·​sphere | \ ˈhe-mə-ˌsfir How to pronounce hemisphere (audio) \

Definition of hemisphere

1a : a half of the celestial sphere as divided into two halves by the horizon (see horizon sense 1b), the celestial equator, or the ecliptic
b : half of a spherical or roughly spherical body (such as a planet) specifically : the northern or southern half of the earth as divided by the equator (see equator sense 2) or the eastern or western half as divided by a meridian (see meridian sense 1a(2)) affected by the weather in the other hemisphere
c : the inhabitants of a hemisphere of the Earth
2 : an area of knowledge or activity : sphere, province a hemisphere of life heretofore unknown to us
3 : one of two half spheres (see sphere entry 1 sense 2a) formed by a plane (see plane entry 1 sense 2a) through the sphere's center : half of a round object
4 : a map or projection of a celestial hemisphere (see hemisphere sense 1a) or a terrestrial hemisphere (see hemisphere sense 1b)
5 : cerebral hemisphere an injury to the left hemisphere

Keep scrolling for more

Other Words from hemisphere

hemispheric \ ˌhe-​mə-​ˈsfir-​ik How to pronounce hemispheric (audio) , -​ˈsfer-​ \ or hemispherical \ ˌhe-​mə-​ˈsfir-​i-​kəl How to pronounce hemispherical (audio) , -​ˈsfer-​ \ adjective

Did You Know?

Hemisphere includes the prefix hemi-, meaning "half". The northern and southern hemispheres are divided by the equator, the circle halfway between Earth's two poles. The eastern and western hemispheres aren't divided so exactly, since there are no poles in the Earth's east-west dimension. Often the dividing line is said to be the "prime meridian"—the imaginary north-south line that runs through Greenwich, England, from which all longitude is calculated (itself being the 0° meridian). But for simplicity's sake, the eastern hemisphere is often said to include all of Europe, Africa, Australia, and Asia, while the western hemisphere contains North and South America and a great deal of ocean.

Examples of hemisphere in a Sentence

a tumor in the right cerebral hemisphere
Recent Examples on the Web But for activists and bystanders in majority-Black and brown neighborhoods across the hemisphere, the curfews and the teargas used against protesters in recent weeks is nothing new. Laura Weiss, The New Republic, "How America Exports Police Violence Around the World," 25 June 2020 Kramp-Karrenbauer made the case that Germany served as a vital forward operating base for U.S. deployments in the hemisphere. Abraham Mahshie, Washington Examiner, "‘Of course, I am ready’: Polish president welcomes US troops from Germany, others will come home," 24 June 2020 The pleasantness of music has been attributed to synchronization of electrical activity in the right hemisphere of the brain. Robert Martone, Scientific American, "Music Synchronizes the Brains of Performers and Their Audience," 2 June 2020 Shifter said the coronavirus has allowed Southcom and the Trump administration to flow assistance to friendly countries in the hemisphere that support U.S. policies. Abraham Mahshie, Washington Examiner, "Ecuador ‘bluff’ buys goodwill from US, not military hardware," 3 June 2020 Synchronous brain activity was localized in the left hemisphere of the brain, to an area known as the temporal-parietal junction. Robert Martone, Scientific American, "Music Synchronizes the Brains of Performers and Their Audience," 2 June 2020 On subjects ranging from China and Russia to Iran and North Korea to tyranny and unrest in our own hemisphere, Senator Rubio has been on the case for years. Mike Brest, Washington Examiner, "Marco Rubio tapped as acting chairman of Senate Intelligence Committee," 18 May 2020 The hull required the forging of two slabs of titanium into perfect hemispheres. Ben Taub, The New Yorker, "Thirty-six Thousand Feet," 10 May 2020 Check out a few of the features inside this week’s magazine: The world needs more America By Dalibor Rohac How the other hemisphere lives By Joel Gehrke Subscribe here for the weekly magazine. Washington Examiner Staff, Washington Examiner, "Inside the magazine: May 5, 2020," 5 May 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hemisphere.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

See More

First Known Use of hemisphere

14th century, in the meaning defined at sense 1a

History and Etymology for hemisphere

Middle English hemispere, from Latin hemisphaerium, from Greek hēmisphairion, from hēmi- + sphairion, diminutive of sphaira sphere

Keep scrolling for more

Learn More about hemisphere

Time Traveler for hemisphere

Time Traveler

The first known use of hemisphere was in the 14th century

See more words from the same century

Statistics for hemisphere

Last Updated

1 Jul 2020

Cite this Entry

“Hemisphere.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hemisphere. Accessed 10 Jul. 2020.

Keep scrolling for more

More Definitions for hemisphere

hemisphere

noun
How to pronounce hemisphere (audio)

English Language Learners Definition of hemisphere

: a half of the Earth
: half of a sphere : half of a round object
technical : either of the two halves of the brain

hemisphere

noun
hemi·​sphere | \ ˈhe-mə-ˌsfir How to pronounce hemisphere (audio) \

Kids Definition of hemisphere

1 : one of the halves of the earth as divided by the equator or by a meridian
2 : a half of a sphere
3 : either the left or the right half of the cerebrum

Other Words from hemisphere

hemispheric \ ˌhem-​ə-​ˈsfir-​ik , -​ˈsfer-​ \ or hemispherical \ -​ˈsfir-​i-​kəl , -​ˈsfer-​ \ adjective

hemisphere

noun
hemi·​sphere | \ -ˌsfi(ə)r How to pronounce hemisphere (audio) \

Medical Definition of hemisphere

: half of a spherical structure or organ: as
b : either of the two lobes of the cerebellum of which one projects laterally and posteriorly from each side of the vermis

Keep scrolling for more

Comments on hemisphere

What made you want to look up hemisphere? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

See Definitions and Examples »

Get Word of the Day daily email!

Test Your Vocabulary

Words for Summer: A Quiz

  • a closeup of a sunflower
  • Which of the following words means “of or relating to summer”?
Spell It

Can you spell these 10 commonly misspelled words?

TAKE THE QUIZ
Dictionary Devil

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!