lon·​gi·​tu·​di·​nal | \ ˌlän-jə-ˈtüd-nəl How to pronounce longitudinal (audio) , -ˈtyüd-, -ˈt(y)ü-dᵊn-əl, British also ˌläŋ-gə-\

Definition of longitudinal

1 : placed or running lengthwise The insect's back is black with yellow longitudinal stripes.
2 : of or relating to length or the lengthwise dimension the longitudinal extent of the building
3 : involving the repeated observation or examination of a set of subjects over time with respect to one or more study variables a longitudinal study of juvenile offenders over a period of five years

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Other Words from longitudinal

longitudinally adverb

Examples of longitudinal in a Sentence

The insect's body is black with yellow longitudinal stripes. calculating the longitudinal position of a ship a longitudinal study of career aspirations among girls from 5 to 17
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Recent Examples on the Web And yet a longitudinal study in 2012 found that marriages in which money was the biggest point of friction were more likely to dissolve than marriages in which other issues loomed larger. Belinda Luscombe, Time, "The New Way to (Finally) Stop Fighting Over Money With Your Spouse," 31 Oct. 2019 This intriguing and pressing question remains unknown due to a dearth of longitudinal studies that follow the same people over time. Kathleen Mullan Harris, The Conversation, "Strong family ties during teen years can help ward off depression in later life," 7 Oct. 2019 In longitudinal studies, data is collected over a number of years. Rod Mccullom, Quartz, "How bullying may shape adolescent brains," 7 Oct. 2019 And in a 2014 longitudinal study, researchers found that U.S. adolescents exposed to suicide in friends and family are more likely to experience suicidal thoughts and, sometimes, attempts. Elizabeth Culotta, Science | AAAS, "Have humans developed natural defenses against suicide?," 22 Aug. 2019 Students will be recruited into the My College Pathways project, a new five-year longitudinal panel. Laura Groch, San Diego Union-Tribune, "CSUSM gets nearly $2M grant to study STEM students," 17 Aug. 2019 And the school just launched a new third-year longitudinal clerkship at MetroHealth, through which urban health students spend their core clinical year at the safety-net hospital. Ginger Christ, cleveland.com, "Doctor shortage to worsen, patients could pay more for fewer options," 11 Aug. 2019 Directional drilling allowed developers to reach the shale, then turn the drill bit axis from perpendicular to longitudinal and lay pipes for a mile, sometimes two, through the thick shale seams. Keith Schneider, ProPublica, "West Virginia Bets Big on Plastics, and on Backing of Trump Administration," 31 July 2019 Large longitudinal studies, meanwhile, require time and money. Sara Talpos, Quartz, "The dangers of energy drinks can be fatal—especially for teens," 10 July 2019

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

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First Known Use of longitudinal

15th century, in the meaning defined at sense 2

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Statistics for longitudinal

Last Updated

15 Nov 2019

Time Traveler for longitudinal

The first known use of longitudinal was in the 15th century

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More Definitions for longitudinal


How to pronounce longitudinal (audio)

English Language Learners Definition of longitudinal

: placed or going along the long side of something
: of or relating to longitude
: done by observing or examining a group of people or things over time to study how one or two particular things about them change


lon·​gi·​tu·​di·​nal | \ ˌlän-jə-ˈtü-dᵊn-əl How to pronounce longitudinal (audio) , -ˈtyü-\

Kids Definition of longitudinal

: placed or running lengthwise longitudinal stripes

Other Words from longitudinal

longitudinally adverb


lon·​gi·​tu·​di·​nal | \ ˌlän-jə-ˈt(y)üd-ᵊn-əl, -nəl, British also ˌläŋ-gə-ˈtyüd-\

Medical Definition of longitudinal

1 : of, relating to, or occurring in the lengthwise dimension a longitudinal bone fracture
2 : extending along or relating to the anteroposterior axis of a body or part a trypanosome which reproduces by longitudinal fission
3 : involving the repeated observation or examination of a set of subjects over time with respect to one or more study variables (as general health, the state of a disease, or mortality) a longitudinal study of heart transplant recipients over a five-year period

Other Words from longitudinal

longitudinally \ -​ē How to pronounce longitudinally (audio) \ adverb

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More from Merriam-Webster on longitudinal

Spanish Central: Translation of longitudinal

Nglish: Translation of longitudinal for Spanish Speakers

Britannica English: Translation of longitudinal for Arabic Speakers

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