incubate

Etymology

It is borrowed from Latin incubō (“to lie on, hatch”),^[2][3][4][5] from its past participle incubātus^[3][6][4] or the participial stem incubāt-, more commonly incubit-,^[2] with the English ending -ate.^[2][3] The Latin verb is formed from in- (“on”) and cubō (“to lie down”),^[7][2][8] the source also of concubine and cubicle; the nasalized stem of the same verb gave incumbent and recumbent.^[8] Ayto suggests that the idea of lying on eggs later fed back into the simple Latin verb, and so produced couvade and covey.^[8]

Earliest recorded meaning

To brood upon, in a figurative sense: the first record is in J. Jackson's True Evangelical Temper (1641).^[2][3][4] Etymonline likewise has the 1640s, with the gloss "to brood upon, watch jealously".^[6]

Semantic evolution

The figurative use is nearly a century older in the record than the literal one: to sit on eggs is not attested until Bailey's dictionary of 1721.^[2][3][6] Johnson (1755) gives only the intransitive use, "to sit upon eggs".^[9] An incubator was at first an apparatus for hatching birds, from 1857,^[3] and the verb was used from 1896 of keeping bacteria warm so that they would grow;^[2] from the early 20th century it meant, more generally, to keep cells or micro-organisms in a controlled environment.^[10] Medicine also uses it for a disease passing through its incubation period,^[2][11] and a figurative use continues, to develop gradually or to foment.^[11][10]

Timeline

• 1641 – transitive and figurative, to brood upon.^[2][3][4]
• 1660 – intransitive and figurative, to brood.^[2]
• 1721 – transitive, to sit on eggs in order to hatch them.^[2][3][6]
• 1755 – intransitive, to sit on eggs.^[2][6]
• 1896 – to place bacteria in an incubator, to keep them at a warmth favourable to growth.^[2]
• 1959 – noun, material that has been incubated.^[2][10]

Meanings

Verb

1. Of a bird, to sit on eggs so as to hatch them with the warmth of the body; to brood.^[11][4][7]
2. To keep eggs, embryos, bacteria or cells under controlled conditions that favour development, especially in an incubator: The lab incubated the cultures for a week.^[11][4][7]
3. Of eggs, embryos, bacteria and the like, to develop under favourable conditions.^[11][10]
4. Of a disease or its germs, to pass through a period in the body before symptoms appear.^[11][2]
5. To develop or cause to develop gradually: an idea that incubated for years.^[11][10]

Noun

1. A preparation or material that has been incubated.^[2][10]

Word family

• incubative
• incubatory
• unincubated
• incubation
• incubator

Related words

• incubus
• succubus

References

1. ^ 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 Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e f g h Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
4. ^ a b c d e f Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
5. ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
6. ^ a b c d e Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
7. ^ a b c The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
8. ^ a b c Ayto, John (2005), Word Origins: The Secret Histories of English Words from A to Z, 2nd ed., London: A & C Black
9. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
10. ^ a b c d e f 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 d e f g Collins English Dictionary (2023), Glasgow: HarperCollins