clamp

Etymology

It is inherited from Middle English clamp,^[2][3] probably borrowed from Middle Dutch clampe (“clamp, cleat”),^{[4][5][6][3][7]} modern Dutch klamp.^[4][5] The OED, the Shorter Oxford and Hoad leave open whether it came from Dutch or Low German,^[8][9][10] and the OED adds that it might be a native word that happens not to be recorded in Old English.^[8] The Germanic word is Proto-Germanic *klampō,^[11] a by-form of the stem of clam according to the OED and Hoad.^[8][10] It is cognate with Middle Low German klampe (“clasp, hook”) and Old High German klampfer (“clip, clamp”),^[4][5] and related to Old English clamm (“bond, fetter”).^[4][5][12] Merriam-Webster also compares Old Norse kleppr (“lump”).^[3] Klein traces the group to Proto-Indo-European *glem- (“to compress, squeeze”), also the source of Latin glomus (“ball”);^[12] Etymonline says perhaps.^[4] The noun took the place of the earlier clam, a clamp or brace, from Old English.^[4] The verb is from the noun,^[8][4][5] like klampen.^[8]

Earliest recorded meaning

A brace or band of metal used for fastening: first in the compound clampclute, apparently an iron piece used as a brace, in a manor document of 1304,^[2][5] then as clampes in an Exchequer account of 1402.^[2][5] The OED's first quotation is from before 1400–50, in the Wars of Alexander,^[8] and Etymonline dates the noun to about 1300.^[4]

Semantic evolution

In Middle English a clamp was a clamp or brace of iron.^[2][8] From the 17th century the word was used of tools with two sides that are screwed together to grip or press something (1688),^[8] and in shipbuilding of the thick planks supporting the ends of the deck beams (1626).^[8][13] The verb, to make fast with a clamp, is recorded from 1677 in Barnhart and 1678 in the OED, in Moxon's Mechanick Exercises;^[5][8] Etymonline puts it in the 1670s and Merriam-Webster in 1683.^[4][3] It came to mean to seize or press firmly (1904),^[8] and clamp down, to take strong measures against something, appears in 1924.^[8] In American slang clamp meant to arrest someone, from 1834.^[14] In British English the verb also means to fix a wheel clamp to a car.^[13] In Scotland clamp could mean to patch clumsily.^[8][15]

Timeline

• 1304 – in the compound clampclute.^[2][5]
• 1402 – clampes, clamps or braces.^[2][5]
• 1626 – nautical, a plank supporting the deck beams.^[8]
• 1677 – verb, to fasten with a clamp.^[5]
• 1688 – a tool with two parts screwed together to grip something.^[8]
• 1834 – US slang, to arrest.^[14]
• 1904 – to seize or press firmly.^[8]
• 1924 – clamp down, to take strong measures.^[8]

Meanings

Noun

1. A device with movable jaws or parts that are brought together, as by a screw, to hold an object firmly or to press two parts together.^[13][3][8]
2. A brace, band or clasp used to strengthen or fasten things together.^[3][8][13]
3. A wheel clamp.^[13]
4. (nautical) A thick plank on a ship's side supporting the ends of the deck beams.^[13][8]

Verb

1. To fasten or hold with a clamp: Clamp the two planks together until the glue sets.^[13][3][8]
2. To grip or hold tightly: She held the pencil clamped between her teeth.^[3][8]
3. To impose something forcefully, often with on: The army clamped a curfew on the city.^[13][3]
4. (British) To fix a wheel clamp to an illegally parked car.^[13]
5. clamp down: to take strict measures to stop or control something, usually with on.^[8][13]

Word family

• C-clamp
• clamper
• unclamp
• clamp down

Related words

• clam
• clump
• climb
• cramp
• clasp

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f Kurath, Hans; Kuhn, Sherman M.; Lewis, Robert E., eds. (1952–2001), Middle English Dictionary, Ann Arbor: University of Michigan Press; online edition ed. Frances McSparran et al. (2000–2018)
3. ^ a b c d e f g h i Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
4. ^ a b c d e f g h i Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
5. ^ a b c d e f g h i j k Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
6. ^ The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
7. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
8. ^ a b c d e f g h i j k l m n o p q r s t u v w Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
9. ^ Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
10. ^ a b Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
11. ^ Orel, Vladimir (2003), A Handbook of Germanic Etymology, Leiden / Boston: Brill
12. ^ a b Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
13. ^ a b c d e f g h i j Collins English Dictionary (2023), Glasgow: HarperCollins
14. ^ a b Green, Jonathon (2010), Green's Dictionary of Slang, London: Chambers; digital ed. 2016–, https://greensdictofslang.com
15. ^ 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)