longitudinal
Pronunciation
Etymology
It is partly borrowed from Middle French longitudinal (“running lengthwise”), recorded in Old French in 1314 as longitudinaus, and partly borrowed from Medieval Latin longitūdinālis (“running lengthwise”), used from the 13th century in British and continental sources.[2][3] The Latin adjective is formed from longitūdō (“length”) and the suffix -ālis;[2][4][5] longitūdō is from longus (“long”), the source of longitude.[3] The OED compares longitudinal and longitudinale.[2] The physical sense of vibrations follows German Longitudinalschwingungen (“longitudinal vibrations”), from a work of the acoustician Chladni (1796).[2]
Earliest recorded meaning
In anatomy, running along the long axis of the body or of a part of it: before 1425, in a translation of Guy de Chauliac's Grande Chirurgie,[2] where the noun is also found for a longitudinal muscle;[2] Etymonline dates the word to the late 14th century,[3] the Merriam-Webster Unabridged to the 15th century,[6] and Dictionary.com to 1535–45.[5]
Semantic evolution
The general sense, running lengthwise along an object, is recorded from 1705,[2] and Johnson (1755) defined the word as "measured by the length; running in the longest direction", noting that it is opposed to transverse.[7] It was used of geographical longitude from 1706,[2] in French already from 1543,[2] and of length as a dimension from 1731.[2] In physics it was applied from 1797 to vibrations, and then to waves whose displacements run in the direction of travel.[2] The noun spread from anatomy to railway sleepers laid along the rails (1838), to the lengthwise members of a ship's frame (1848) and to the longerons of an airship (1908).[2] The sense "carried on over a long period", of a scientific study with repeated observations, dates from 1913.[2][8]
Timeline
- before 1425 – in anatomy, running along the long axis of the body; noun, a longitudinal muscle.[2]
- 1705 – running lengthwise.[2]
- 1706 – relating to geographical longitude.[2]
- 1731 – relating to length as a dimension.[2]
- 1797 – of vibrations, along the length of the vibrating body.[2]
- 1838 – noun, a railway sleeper laid along the rails.[2]
- 1848 – noun, a lengthwise member of a ship's frame.[2]
- 1913 – of a study, extending over a long period.[2]
Meanings
Adjective
- Running or placed lengthwise; extending along the long axis of something: longitudinal stripes.[8][6][2]
- Of or relating to length as a dimension.[8][6][2]
- Of or relating to longitude.[8][2]
- Of a wave, with its particles displaced in the direction in which the wave travels.[2][6]
- Of a study, carried on over a long period with repeated observations of the same subjects.[8][2]
Noun
- In shipbuilding, one of the fore-and-aft girders in a ship's frame.[6][2]
- In aeronautics, a longeron.[6][2]
- In anatomy, a body part such as a muscle, nerve or sinus that runs lengthwise.[6][2]
Word family
- longitudinally
- longitudinal wave
Related words
- longitude
- long
- latitudinal
- transverse
References
- ^ a b Wiktionary, the free dictionary, https://en.wiktionary.org
- ^ a b c d e f g h i j k l m n o p q r s t u v w x y z 27 28 29 Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
- ^ a b c Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
- ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
- ^ a b Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
- ^ a b c d e f g Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
- ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
- ^ a b c d e Collins English Dictionary (2023), Glasgow: HarperCollins