effusion

Etymology

It is inherited from Middle English effusioun,^[2][3] borrowed from Old French effusion and directly borrowed from Latin effūsiō (“a pouring forth”).^[4][3][5][6] The OED treats Latin as the source, directly or through French,^[4] and the French word is recorded in the 14th century.^[4][3] There is already Anglo-Norman effusiun from the first half of the 12th century, for an outpouring of water and for the shedding of blood.^[7] The Latin noun of action comes from effundō (“to pour forth, spread abroad”),^[3][8] formed from ex- (“out”) and fundō (“to pour”),^[3][5][9] from a nasalized form of Proto-Indo-European *gheu- (“to pour”).^[3]

Earliest recorded meaning

The OED's first quotation, from the Chester Plays and dated uncertainly to before 1400, uses it of people, for a dispersal or rout.^[4] The plainer record is 1402, when Hoccleve wrote of the spilling of blood;^[2][5] the Dictionary.com dating runs 1350–1400.^[10]

Semantic evolution

Its early use was for blood: effusion of blood meant bloodshed or slaughter.^[2][4] It spread to other outflows: smoke or vapours (about 1477–1667),^[4] a generous gift, Johnson's "bounteous donation" (1514–1654),^[4] then from 1548 a pouring forth of an influence, often of the Holy Spirit.^[4] The sense of speech and feeling, with words flowing out unchecked, appears in the 1650s.^[3][4] Johnson (1755) lists the pouring out of liquids, waste or spilling, and the pouring out of words.^[11] In 1781 Johnson himself applied it to a literary work, regarded as the outpouring of its author's feelings or genius,^[4] while from 1878 it could mean an effusive manner, as in French.^[4] Science took the word in two directions: in pathology, for fluid escaping from its natural vessel (1732),^[4] and in physics, for a gas passing through a small opening (Graham, 1858).^[4]

Timeline

• c. 1400 – of people, a dispersal or rout (obsolete by 1726).^[4]
• 1402 – a spilling of blood.^[2][5] The OED's first quotation for a pouring out of liquid is from about 1440.^[4]
• c. 1477 – a copious emission of smoke or vapours (obsolete by 1667).^[4]
• 1514 – a generous gift (obsolete by 1654).^[4]
• 1548 – a pouring forth of an influence, often of the Holy Spirit.^[4]
• 1659 – unrestrained utterance of words or feelings.^[4]
• 1732 – in pathology, the escape of fluid from its vessel.^[4]
• 1781 – a literary work or speech as an outpouring of feeling.^[4]
• 1858 – in physics, the passage of a gas through a small opening.^[4]
• 1878 – an effusive manner.^[4]

Meanings

Noun

1. An unrestrained outpouring of words or feeling: She dreaded another effusion of praise from her aunt.^[12][4]
2. A piece of writing or a speech seen as such an outpouring.^[4]
3. The act of pouring out, or the state of being poured out: the effusion of blood.^[12][6][4]
4. Something that has been poured out.^[12]
5. (medicine) The escape of blood or another fluid into a body cavity or tissue; also the fluid itself.^[12][6][4]
6. (physics) The flow of a gas under pressure through a very small aperture.^[12][4]

Word family

• noneffusion

Related words

• effusive
• effuse
• fusion
• affusion
• found
• confuse
• diffuse
• infuse
• transfuse

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d 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 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 o p q r s t u v w x y z 27 28 Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
5. ^ a b c d Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
6. ^ a b c Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
7. ^ Anglo-Norman Dictionary (AND2), Aberystwyth University, anglo-norman.net (2nd ed., 2005–)
8. ^ Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
9. ^ Weekley, Ernest (1921), An Etymological Dictionary of Modern English, London: John Murray
10. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
11. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
12. ^ a b c d e Collins English Dictionary (2023), Glasgow: HarperCollins