plexus

Etymology

It is borrowed from New Latin plexus,^[2][3][4] a post-classical Latin word for an interwoven structure in the body, recorded from 1543 or earlier,^[4] from plexus (“plaited, twined”), the past participle of plectō (“to plait, twine, braid”).^[4][3][5][6] Etymonline and the American Heritage Dictionary trace the Latin verb to Proto-Indo-European *plek- (“to plait”),^[3][5] which the OED connects with the root of fold and of flehtan in Old High German.^[4] Barnhart thinks the New Latin word and its borrowing into English were probably influenced by French plexus, which he finds as early as 1560;^[2] the OED dates the French word to 1575, in Paré.^[4] The OED adds that in classical Latin plexus as a noun, "plaiting, braid", is only a doubtful variant reading, though it lives on in compounds such as amplexus and complex.^[4]

Earliest recorded meaning

In anatomy, a network of fibres or vessels: 1666, in Samuel Parker's Account of the Divine Dominion and Goodness.^[4][7] Barnhart dates the word to 1682 and Etymonline to the 1680s.^[2][3]

Semantic evolution

Etymonline says the word was first used in solar plexus, the network of nerves in the abdomen.^[3] The general sense of any intricate, interwoven arrangement followed from 1769.^[4][3][8] A mathematical use, a system of mathematical relations, is recorded from 1860 in Cayley but is now rare.^[4] Weekley notes that the solar plexus was a favourite target of boxers.^[9]

Timeline

• 1666 – a network of nerves, blood vessels or fibres in the body.^[4][7] Barnhart dates the word to 1682.^[2]
• 1769 – any intertwined mass or intricate network.^[4][3]
• 1860 – in mathematics, a system of relations (now rare).^[4]

Meanings

Noun

1. In anatomy, a network of interlacing nerves, blood vessels or lymphatic vessels: the nerves of the brachial plexus.^[10][7][4]
2. Any complex, interwoven network or arrangement of parts: a plexus of family loyalties and old debts.^[10][7][4]

Word family

• plexiform
• cervical plexus

Related words

• complex
• perplex
• ply
• plait
• amplexus
• solar plexus

Usage notes

The plural is plexuses, or plexus as in Latin.^[10][8]

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
3. ^ a b c d e f g Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b c d e f g h i j k l m n Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
5. ^ a b The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
6. ^ Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
7. ^ a b c d Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
8. ^ a b Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
9. ^ Weekley, Ernest (1921), An Etymological Dictionary of Modern English, London: John Murray
10. ^ a b c Collins English Dictionary (2023), Glasgow: HarperCollins