lest

Etymology

It is inherited from Middle English leste,^[2][3][4] inherited from Old English þē lǣste,^[5][6][7] a shortening of the older phrase þȳ lǣs þe (“whereby less that”).^{[8][9][5][10][3]} In the phrase, þȳ is the instrumental of the demonstrative þæt (“that”), lǣs is the source of less, and þe is the relative particle, related to the.^{[2][3][9][10][5]} The first word was dropped, and the remaining two were contracted, with dissimilation of the consonant cluster;^[8][7][4][3] the OED compares the same change in nostril, and shows that the contracted form was already in use in late Old English.^[8] The OED and Weekley compare the Latin construction quōminus, which Weekley thought the Old English phrase might translate.^[8][11] Johnson derived the word from the adjective least.^[12]

Earliest recorded meaning

So that not, introducing something to be prevented or guarded against: about 1175, in an Old English homily copied in MS Bodley 343.^[8] Barnhart dates the contracted form leste probably before 1200, in Layamon's chronicle, and Etymonline about 1200.^[13][3]

Semantic evolution

Etymonline glosses the early sense as "that not", especially "for fear that".^[3] From before 1225 it was also used after verbs of fearing or words expressing danger, to introduce the event feared, where it means simply "that".^[8][7] The combination lest that was used from the 15th century until the early 19th, and is now obsolete.^[8][7] Johnson (1755) explained it as "that not", quoting the Bible.^[12] Lest has become formal: it is one of the few places in English where the subjunctive is still required, as in lest he be attacked,^[14][15] and it is also followed by should.^[15]

Timeline

• c. 1175 – so that not, introducing a thing to be prevented.^[8]
• before 1200 – the contracted form leste, in Layamon.^[13]
• before 1225 – after verbs of fearing, that.^[8]
• c. 1450–1825 – lest that (obsolete).^[8]

Meanings

Conjunction

1. So as to prevent something; in order that not: She wrote the date down lest she forget it.^{[15][10][8][14]}
2. After words expressing fear or anxiety: that; for fear that: They were anxious lest the bridge should collapse.^[15][10][8]

Related words

• less
• least
• the
• that

Usage notes

Lest is formal and is followed by a verb in the subjunctive or by should; the standard use is lest he be attacked rather than lest he was attacked.^[14][15]

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b Barnhart, Robert K., ed. (1995), The Barnhart Concise Dictionary of Etymology, New York: HarperCollins
3. ^ a b c d e f Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
5. ^ a b c Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
6. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
7. ^ a b c d Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
8. ^ a b c d e f g h i j k l Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
9. ^ a b The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
10. ^ a b c d Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
11. ^ Weekley, Ernest (1921), An Etymological Dictionary of Modern English, London: John Murray
12. ^ 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.
13. ^ a b Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
14. ^ a b c Soanes, Catherine; Stevenson, Angus, eds. (2004), Concise Oxford English Dictionary, 11th ed., Oxford: Oxford University Press
15. ^ a b c d e Collins English Dictionary (2023), Glasgow: HarperCollins