slacken

Etymology

It is formed from English slack + -en.^[2][3][4][5] Etymonline thinks it was formed after the specialised sense of slake.^[3] The OED compares Icelandic slakna, and the rarer slaken, recorded from 1303 to 1675 and formed from the adjective slake.^[2] The adjective slack is from Old English slæc (“remiss, lax, sluggish”), from Proto-Germanic *slakas, from Proto-Indo-European *sleg- (“to be slack, languid”).^[3]

Earliest recorded meaning

To cause to become slower; to delay or retard: 1580, in Hollyband's French dictionary.^[2] Etymonline likewise has the 1570s,^[3] and Dictionary.com 1570–80,^[5] but Merriam-Webster Unabridged gives the 14th century.^[6]

Semantic evolution

By 1605, in Bacon, it meant to relax in strictness,^[2] and by 1611, in Cotgrave, to make a rope or the like less taut.^[2] Before 1631 Donne used it for making something less vigorous.^[2] Intransitive uses, to become less energetic, followed from the 1610s,^[3] or the mid-17th century in the Shorter Oxford.^[4] Johnson (1755) gave it as "to loosen; to make less tight", "to relax; to remit" and "to ease; to mitigate", and thought Philips had used it by mistake for slake.^[7] In English dialect it could also mean to fall in price, to quench, and to reduce; a slacken-twist was a dawdler in Warwickshire.^[8]

Timeline

• 1580 – to make slower, to delay.^[2]
• 1605 – to relax in strictness.^[2]
• 1610s – intransitive, to become lax or less energetic.^[3]
• 1611 – to make less tense or taut.^[2]
• before 1631 – to make less vigorous.^[2]
• 1685 – to moderate, make less intense.^[2]
• 1749 – to let one's pace fall off.^[2]
• 1815 – to loosen.^[2]

Meanings

Verb

1. To make or become slower: The cyclists slackened their speed on the hill.^[9][6][2]
2. To make or become less tense or taut; to loosen: He slackened the guy ropes before the storm.^[9][6][4][2]
3. To make or become less vigorous, intense or severe; to abate: The rain slackened towards evening.^[9][4][2]
4. To become remiss, negligent or less energetic.^[6][4][10]
5. (dialect) To fall in price.^[8]

Word family

• unslackened
• unslackening

Related words

• slack
• slacker
• slake
• languid

Usage notes

A separate noun slacken, slag mixed with ores in smelting, was borrowed from German Schlacken and is recorded from 1670.^[2][6] It is a technical word with its own origin, unrelated to the verb.^[2][6]

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 Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b c d e Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
5. ^ a b Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
6. ^ a b c d e f Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
7. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
8. ^ a b Wright, Joseph, ed. (1898–1905), The English Dialect Dictionary, 6 vols., Oxford: Henry Frowde; via EDD Online 4.0, University of Innsbruck (CC BY 4.0)
9. ^ a b c The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
10. ^ The Chambers Dictionary (2014), 13th ed., Edinburgh: Chambers