longitudinal

adjective

lon·​gi·​tu·​di·​nal ˌlän-jə-ˈtüd-nəl How to pronounce longitudinal (audio)
-ˈtyüd-,
-ˈt(y)ü-dᵊn-əl,
 British also  ˌläŋ-gə-
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
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
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The luxury automaker focused on five components to deliver that thrilling drive: sound, gear change, longitudinal acceleration, braking and lateral acceleration. Eileen Falkenberg-Hull, MSNBC Newsweek, 9 Oct. 2025 The report also offers one of the most comprehensive longitudinal views of CEO sentiment on sustainability, just as the UN Global Compact enters its 25th year, the organizations said. Jasmin Malik Chua, Sourcing Journal, 8 Oct. 2025 Elise Christopher oversaw the high school longitudinal studies at the National Center for Education Statistics, part of the Institute of Education Sciences, until she was laid off in March along with dozens of her colleagues. Carmela Guaglianone, NPR, 7 Oct. 2025 Exchange Relationships In the massive longitudinal study, Park and his colleagues followed more than 7,000 couples over the course of 13 years. Mark Travers, Forbes.com, 18 Sep. 2025 See All Example Sentences for longitudinal

Word History

First Known Use

15th century, in the meaning defined at sense 2

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

Cite this Entry

“Longitudinal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/longitudinal. Accessed 23 Oct. 2025.

Kids Definition

longitudinal

adjective
lon·​gi·​tu·​di·​nal ˌlän-jə-ˈt(y)üd-nəl How to pronounce longitudinal (audio)
-ᵊn-əl
1
: of or relating to length
2
: placed or running lengthwise
longitudinally
adverb

Medical Definition

longitudinal

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

More from Merriam-Webster on longitudinal

Last Updated: - Updated example sentences
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