longitude

noun lon·gi·tude \ ˈlän-jə-ˌtüd , -ˌtyüd , British also ˈläŋ-gə- \

|Updated on: 27 Jun 2018

Definition of longitude

1 a : angular distance measured on a great circle of reference from the intersection of the adopted zero meridian with this reference circle to the similar intersection of the meridian passing through the object

b : the arc or portion of the earth's equator intersected between the meridian of a given place and the prime meridian and expressed either in degrees or in time

2 archaic : long duration

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Examples of longitude in a Sentence

a map of the world showing lines of latitude and longitude
calculating the longitudes of different places
The regions are on roughly the same longitude.

Recent Examples of longitude from the Web

The lines that are already on the basketball are like lines of longitude.

— rhett allain, WIRED, "Figure Out Where You Are With Nothing But a Watch and Protractor," 3 May 2018
The data include estimates of the latitude and longitude of each named storm's center at six-hour intervals.

— Anchorage Daily News, "Hurricanes are moving more slowly. That makes them more dangerous.," 6 June 2018
Working with Frank, Turton and Beneduce determined the photo’s exact location using the longitude and latitude from the images and even enlisted the help of an oceanographer to determine just how the sign traveled so far.

— char adams, PEOPLE.com, "N.J. Realty Sign Lost in Hurricane Sandy Found in France 5 Years Later: 'I Couldn't Believe It'," 1 June 2018
The interactive site also shows rotor diameter and hub height, turbine models and their positions by latitude and longitude.

— jim efstathiou jr, Bloomberg.com, "A Wind Lover's Dream: All 57,636 U.S. Wind Turbines on One Map," 20 Apr. 2018
This time difference is essentially your longitude.

— rhett allain, WIRED, "Figure Out Where You Are With Nothing But a Watch and Protractor," 3 May 2018
But as one gets close to the poles, lines of longitude converge and the system breaks down.

— NBC News, "Einstein made his share of errors. Here are three of the biggest," 14 Mar. 2018
Harrison was self-educated, and is credited with creating the first marine chronometer to calculate longitude when sailors were at sea.

— mackenzie cummings-grady, Billboard, "Google Doodle Celebrates Famous Clockmaker John Harrison," 3 Apr. 2018
Tied around their legs were specimen labels: faded, handwritten records of the date, altitude, latitude, and longitude of their capture, along with other vital details.

— Outside Online, "The Curious Case of the Fly-Fishing Feather Thief," 19 Apr. 2018

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

Did You Know?

The imaginary (but very important) lines of longitude run from the North Pole to the South Pole. Each is identified by the number of degrees it lies east or west of the so-called prime meridian in Greenwich, England (part of London). A circle is divided into 360°; so, for example, the longitude of the Egyptian city of Cairo is about 31°E—that is, about 31° east of London. The "long" sense of the root may be easier to see in some uses of the adjective longitudinal: A longitudinal study is a research study that follows its subjects over many long years, and a longitudinal engine is one that drives a crankshaft that runs lengthwise under a vehicle (as in rear-wheel-drive cars) rather than crosswise.

Illustration of longitude

Origin and Etymology of longitude

Middle English, from Latin longitudin-, longitudo, from longus

NEW! Time Traveler

First Known Use: 15th century

in the meaning defined at sense 1a

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LONGITUDE Defined for English Language Learners

longitude

noun

Definition of longitude for English Language Learners

: distance measured in degrees east or west from an imaginary line (called the prime meridian) that goes from the North Pole to the South Pole and that passes through Greenwich, England
: an imaginary line that circles the Earth at a particular longitude

LONGITUDE Defined for Kids

longitude

noun lon·gi·tude \ ˈlän-jə-ˌtüd , -ˌtyüd \

Definition of longitude for Students

: distance measured in degrees east or west of an imaginary line that runs from the north pole to the south pole and passes through Greenwich, England