skylight

Etymology

It is formed from English sky + light.^{[2][3][4][5][6]} Etymonline notes that it was also written with a hyphen.^[3]

Earliest recorded meaning

A light in the sky, or a body in the sky that gives or reflects light: 1574, in A. Golding's translation of Calvin's sermons on Job.^[2] Etymonline dates the word, as "light from the sky", to the 1670s.^[3]

Semantic evolution

The first senses were about the sky itself: a light in the sky (1574 to 1899), the daylight that comes from the sky (from 1632), and, at sea, the light of the night sky (1644 to 1730).^[2] From about 1660 the word was used for a window set in a roof or ceiling to let daylight in,^[2] a sense Etymonline dates to the 1680s and the 1989 edition of the OED to 1690.^[3][7] Johnson (1755) defined it as a window placed not in the side of a room but in the ceiling.^[6] At sea it named a glazed frame in the deck that lets light down into the cabins,^[8][9] and in slang it was briefly the space left at the top of a glass, to be filled before a toast (1753 to 1850), and an eye (1824 to 1833).^[2] A verb, to fit a roof with a skylight, appears in Dickens's Pickwick Papers (1836);^[2] the OED marks it obsolete, but Merriam-Webster Unabridged still lists it.^[2][9] In the 20th century the noun gained the adjective sky-lit (1923)^[3] and the photographers' skylight filter, a nearly colourless filter that cuts the blue cast of light from the sky.^[4]

Timeline

• 1574 – a light or shining body in the sky (obsolete by 1899).^[2]
• 1632 – the daylight that comes from the sky.^[2] Etymonline dates this sense to the 1670s, and Merriam-Webster Unabridged to 1679.^[3][9]
• 1644 – the light of the night sky (obsolete).^[2]
• c. 1660 – a window in a roof or ceiling.^[2] Etymonline dates it to the 1680s.^[3]
• 1705 – figurative use.^[2]
• 1753 – the gap at the top of a glass, filled before a toast (obsolete by 1850).^[2]
• 1824 – slang, an eye (obsolete).^[2]
• 1836 – verb, to provide a roof with a skylight.^[2]

Meanings

Noun

1. A window set into a roof or ceiling to let in daylight: A skylight brightened the narrow attic stairs.^{[10][9][11][2]}
2. A similar glazed opening in the deck of a ship, letting light into the rooms below.^[9][12][8]
3. The diffuse light of the sky, scattered and reflected by the atmosphere.^[9][12][2]
4. The faint background light of the night sky, from natural and artificial sources; airglow.^[9]

Verb

1. To light a room, or fit a roof, with a skylight.^[9][2]

Word family

• skylighted

Related words

• sky
• light
• daylight
• fanlight

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 q r Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e f g Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
5. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
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. ^ Simpson, J. A.; Weiner, E. S. C., eds. (1989), The Oxford English Dictionary, 2nd ed., Oxford: Clarendon Press
8. ^ a b Smyth, W. H. (1867), The Sailor's Word-Book: An Alphabetical Digest of Nautical Terms, London: Blackie and Son
9. ^ a b c d e f g h Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
10. ^ Collins English Dictionary (2023), Glasgow: HarperCollins
11. ^ The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin
12. ^ a b Merriam-Webster's Collegiate Dictionary (2003), 11th ed., Springfield, Mass.: Merriam-Webster