lobe

Etymology

It is borrowed from Medieval Latin lobus (“lobe”),^[2][3][4] from Late Latin lobus (“hull, husk, pod”),^[2][4][5][6] from Ancient Greek λοβός (lobós, “lobe of the ear or liver; pod”).^{[7][2][4][8][9]} Barnhart, Merriam-Webster and Klein see also Middle French lobe,^[4][10][8] which the OED dates to the 16th century.^[7] The origin of the Greek word is unclear.^[2] The OED takes it from an earlier Proto-Indo-European *logw-, cognate with *legw- in Latin legūmen (“pod”) and lēgula (“lobe of the ear”),^[7][11] the source of legume.^[11] Klein relates it to Ancient Greek λέβινθοι (lébinthoi, “peas”) and λεβηρίς (lebērís, “husk”), and to a root seen in λέπω (lépō, “to peel”).^[8] Etymonline cites Beekes, who finds a link with the source of lap semantically attractive.^[2]

Earliest recorded meaning

One of the divisions of the lungs or the liver: before 1425, in a Middle English translation of Guy de Chauliac's surgery, which gives the lungs five lobes.^[3][4] The OED's first record is from about 1541, in Copland's Questyonary of Cyrurgyens.^[7] Etymonline dates the word to the early 15th century.^[2]

Semantic evolution

The Greek word was used of lap-like parts of the body and of plants, above all the lobe of the ear, and also of pods.^[2][11] In English the anatomical sense came first, and was extended to the brain in 1672.^[7][2] In botany it meant a pod or seed case from 1672 (now obsolete), and then a rounded division of a leaf.^[7] The lobe of the ear is recorded from 1719.^[7] Johnson (1755) defined the word as "a division; a distinct part", used commonly of the lungs.^[12] Later uses include the projecting part of a cam (1855), a great projection from an ice sheet (1889), a portion of an aerial's radiation pattern (1926) and a curved part of a letter in calligraphy (1957).^[7][2] Etymonline sums up the common notion as "rounded protruding part".^[2]

Timeline

• before 1425 – a division of the lungs or liver.^[3][4] The OED dates this sense to about 1541.^[7]
• 1672 – a division of the brain; in botany, a pod (now obsolete) and a rounded division of a leaf.^[7]
• 1719 – the soft lower part of the outer ear.^[7]
• 1826 – in zoology, a rounded projection of an organ.^[7]
• 1855 – the projecting part of a cam wheel.^[7]
• 1889 – a projection from the edge of an ice sheet.^[7][2]
• 1926 – a part of the radiation pattern of an aerial.^[7]
• 1957 – in calligraphy, a curved projecting part of a letter.^[7]

Meanings

Noun

1. A rounded part that projects from a larger structure.^[13][10][7]
2. A division of an organ such as the brain, lung or liver, marked off by a fissure or by connective tissue: the frontal lobe.^[13][10][7]
3. The soft lower part of the outer ear; an earlobe.^[13][10][7]
4. A rounded division of a leaf or other plant part.^[13][10][7]
5. One of the loops of the radiation pattern of an aerial, in a direction of stronger radiation.^[13][7]
6. The projecting part of a cam wheel.^[7]

Word family

• earlobe
• lobar
• lobate
• lobation
• lobectomy
• lobed
• lobefin
• lobule

Related words

• lobotomy
• legume

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
3. ^ a b c Kurath, Hans; Kuhn, Sherman M.; Lewis, Robert E., eds. (1952–2001), Middle English Dictionary, Ann Arbor: University of Michigan Press; online edition ed. Frances McSparran et al. (2000–2018)
4. ^ a b c d e f Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
5. ^ The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
6. ^ Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
7. ^ a b c d e f g h i j k l m n o p q r s t u v Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
8. ^ a b c Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
9. ^ Weekley, Ernest (1921), An Etymological Dictionary of Modern English, London: John Murray
10. ^ a b c d e Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
11. ^ a b c Ayto, John (2005), Word Origins: The Secret Histories of English Words from A to Z, 2nd ed., London: A & C Black
12. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
13. ^ a b c d e Collins English Dictionary (2023), Glasgow: HarperCollins