sentinel

Etymology

It is borrowed from Middle French sentinelle,^[2][3][4][5] from Italian sentinella.^{[2][3][6][5][7]} centinela and sentinella come from the Italian or the French word.^[2] The origin of the Italian word is unknown according to the OED, Barnhart, Hoad and the “Oxford Dictionary of English”;^[2][3][5][7] the OED argues from its feminine gender that it first meant either the keeping of watch or a sentry box or watchtower, like the French words behind spy, scout and guard.^[2] Merriam-Webster and the American Heritage Dictionary derive it, probably, from Old Italian sentina (“vigilance”), from sentire (“to perceive, watch”), from Latin sentiō (“to feel, perceive”),^[4][8][9] and Etymonline and Klein also connect it with sentire, through the idea of perceiving and watching.^[6][10] Skeat thought it apparently from the Latin verb, but uncertain.^[11] Weekley took the Italian word as a diminutive of sentina (“latrine”), a nickname for a sentry box on a rampart, since an outside latrine looked much like one; he held that sentry has a separate source, though the two were always associated.^[12]

Earliest recorded meaning

A soldier posted to keep guard, a sentry: 1579, in the Digges' military treatise Stratioticos.^[2][3][4]

Semantic evolution

In the late 16th century the word could also mean the duty of keeping watch, as in to keep sentinel (1585 to 1703),^[2][6][12] and a watchtower on a city wall, a sense found in Philemon Holland's translation of Livy (1600).^[2][12] The figurative use, anything that keeps guard like a sentinel, appears in 1594 in Marlowe and Nashe's Dido.^[2] The verb, formed from the noun, is first recorded in 1593 in Nashe, meaning to keep guard,^[2] and in 1594 in Shakespeare's Lucrece, meaning to stand guard over.^[2][3] Weekley records the spellings centinel and centronel, the latter probably influenced by century, a detachment of troops.^[12] From 1710 to the late 19th century private sentinel or centinel meant a private soldier.^[2][5] Johnson (1755) defined the word as one who keeps guard to prevent surprise, quoting Shakespeare's Richard III.^[13] Collins records a sense in computing, a character that marks the beginning or end of a block of information.^[9]

Timeline

• 1579 – a soldier posted as a guard.^[2][3][4]
• 1585 – the duty of keeping watch (obsolete by 1703).^[2]
• 1593 – verb, to keep guard.^[2][4]
• 1594 – figurative, something that keeps guard; verb, to stand guard over.^[2]
• 1600 – a watchtower (obsolete by 1643).^[2]
• 1656 – verb, to provide with a sentinel.^[2]
• 1710 – private sentinel, a private soldier (obsolete by 1894).^[2]
• 1827 – verb, to post as a sentinel.^[2]
• 1904 – a nautical sense.^[2]

Meanings

Noun

1. A soldier or guard posted to keep watch; a sentry: A sentinel stood at each gate of the fort.^[9][4][2]
2. A person or thing that watches over or guards something: Tall pines stood like sentinels along the ridge.^[2][4]
3. An officer of a secret society posted outside the door of a meeting to keep out those not entitled to enter.^[4]
4. (computing) A character that marks the beginning or end of a block of information.^[9]
5. (obsolete, 1585–1703) The duty of keeping watch; guard.^[2][4]
6. (obsolete, 1600–1643) A watchtower.^[2][4][5]
7. (obsolete, 1710–1894) A private soldier.^[2][5]

Verb

1. To stand guard over; to watch over as a sentinel.^[4][9][2]
2. To provide with a sentinel or sentinels.^[4][9][2]
3. To post as a sentinel.^[4][9][2]

Word family

• sentinellike
• sentinelship

Related words

• sentry
• sense

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 s t u v w x y z 27 28 29 Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e f Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
4. ^ a b c d e f g h i j k l m Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
5. ^ a b c d e f Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
6. ^ a b c Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
7. ^ a b Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
8. ^ The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
9. ^ a b c d e f g Collins English Dictionary (2023), Glasgow: HarperCollins
10. ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
11. ^ Skeat, Walter W. (1911), A Concise Etymological Dictionary of the English Language, new ed., Oxford: Clarendon Press
12. ^ a b c d Weekley, Ernest (1921), An Etymological Dictionary of Modern English, London: John Murray
13. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.