multiplicity

Etymology

It is inherited from Middle English multiplicite,^[2][3] partly borrowed from Middle French multiplicité (“a large number, manifold variety”) and partly borrowed from Late Latin multiplicitās,^[4][5][6] which is formed from the stem of Latin multiplex (“manifold, many times as great”) and -itās.^[4][6][7] The Old French word is recorded about 1190 as multipliciteit, and the Latin one from the 5th century.^[4] Multiplex is made from multus (“much, many”) and the base of plicō (“to fold”),^[7] from Proto-Indo-European *plek- (“to plait”).^[3] The OED compares the earlier duplicity and simplicity,^[4] and the Latin word is also the source of Italian molteplicità and Spanish multiplicidad.^[4]

Earliest recorded meaning

The quality of being manifold, great variety: about 1454, in Pecock's Folewer to Donet, which speaks of "multiplicite and dyuersite of wordis".^[4][2] Etymonline dates the word to the mid-15th century,^[5] and Dictionary.com to 1580–90.^[8]

Semantic evolution

From 1587 the word could name an instance of manifoldness, and since 1601 it was used with of for a large number or variety of things.^[4][9] Johnson (1755) defined it as "more than one of the same kind", quoting a writer who argued against "a multiplicity of gods".^[10] From the 19th century it took technical senses: in mathematics the number of times a root occurs (1841), in medicine the presence of several centres of a disease (1851), in physics the number of components of a multiplet (1923), and in biology, from 1947, the multiplicity of infection, the number of virus particles added per host cell.^[4]

Timeline

• c. 1454 – the quality of being manifold, manifold variety.^[4][2]
• 1587 – an instance of this.^[4]
• 1601 – a large number or variety of things.^[4]
• 1841 – (mathematics) the number of times a root occurs.^[4]
• 1851 – (medicine) the presence of several foci of disease.^[4]
• 1923 – (physics) the number of components of a multiplet.^[4][9]
• 1947 – (biology) in multiplicity of infection.^[4]

Meanings

Noun

1. A large number or great variety: a multiplicity of local dialects.^[9][11][4]
2. The state of being multiple or manifold.^[9][6][11]
3. (mathematics) The number of times a given root occurs as a factor of a polynomial.^[4][6]
4. (physics) The number of energy levels into which an atom, molecule or nucleus splits, or the number of components of a multiplet.^[9][4]

Related words

• multiple
• multiplex
• multiply
• duplicity
• simplicity
• complex

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ 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)
3. ^ a b The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
4. ^ a b c d e f g h i j k l m n o p q r Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
5. ^ a b Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
6. ^ a b c d Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
7. ^ a b Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
8. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
9. ^ a b c d e Collins English Dictionary (2023), Glasgow: HarperCollins
10. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
11. ^ a b The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin