operant

Etymology

It is borrowed from Late Latin operāns (“active, effective”),^[2] the adjectival use of the present participle of operor (“to work, labour”),^[2][3][4][5] from opera (“work, effort”), related to opus (“a work”), from Proto-Indo-European *op- (“to work, produce in abundance”).^[3] The OED finds the adjective in Tertullian, in the early 3rd century,^[2] and in Late Latin the verb also came to mean to have effect or be active.^[3] The OED compares Middle French opérant, recorded from 1470,^[2] and Johnson derived the word from French.^[6]

Earliest recorded meaning

Working, producing an effect: about 1425, in a translation of Guy de Chauliac, where "cause operant" renders the Latin causa operante.^[5][2] Etymonline likewise has the early 15th century,^[3] and Merriam-Webster Unabridged the 15th century.^[7] Barnhart, without the medieval record, starts with Shakespeare's Hamlet in 1602,^[8] and Dictionary.com dates the word to 1595–1605.^[9]

Semantic evolution

In early use the word could mean powerful in effect, a sense now gone: Shakespeare's Timon of Athens has "thy most operant poison".^[10][2] Johnson (1755) quotes that line and calls it "a word not in use".^[6] The noun, a person or thing that operates, is recorded from 1700,^[2][8] and Lamb used it in 1831 for a workman.^[2] The word found its modern home in psychology, when B. F. Skinner in 1937 applied it to behaviour that is spontaneous rather than a response to a stimulus and that is reinforced or inhibited by its own consequences,^[2][8][3] to distinguish it from behaviour that responds to a stimulus.^[8] Etymonline dates operant conditioning to 1938, also in Skinner.^[3]

Timeline

• c. 1425 – working, producing an effect, in "cause operant".^[5][2]
• 1700 – noun, a person or thing that operates (OED: obsolete, last 1871).^[2][8]
• 1831 – noun, a workman, in Lamb.^[2]
• 1937 – in psychology, adjective and noun, in B. F. Skinner.^[2][8][3]
• 1938 – operant conditioning, in Skinner, as Etymonline dates it.^[3]

Meanings

Adjective

1. Working or tending to produce an effect; effective, operative: an operant motive.^[11][7][2]
2. (psychology) Of or being behaviour that is changed by the reinforcing or inhibiting effect of its own consequences, as in operant conditioning.^[7][2][4]
3. Of or relating to what is observable or measurable.^[7][12]

Noun

1. (psychology) An item of behaviour that arises spontaneously rather than in response to a stimulus and that acts on the environment to produce consequences.^[11][7][2]
2. A person or thing that operates; an operator.^[11][7][8] The OED marks this sense obsolete and rare.^[2]

Word family

• operantly
• operant conditioning

Related words

• operate
• operation
• operative
• operator
• opus
• opera

References

1. ^ a b Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k l m n o p q Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e f g h Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
5. ^ 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)
6. ^ a b Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
7. ^ a b c d e f Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
8. ^ a b c d e f g Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
9. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
10. ^ Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
11. ^ a b c Collins English Dictionary (2023), Glasgow: HarperCollins
12. ^ Merriam-Webster's Collegiate Dictionary (2003), 11th ed., Springfield, Mass.: Merriam-Webster