\ ˈkȯk How to pronounce caulk (audio) \
variants: or
caulked or calked; caulking or calking; caulks or calks

Definition of caulk

 (Entry 1 of 3)

transitive verb

: to stop up and make tight against leakage (something, such as a boat or its seams, the cracks in a window frame, or the joints of a pipe)


noun (1)
variants: or calk or less commonly caulking or calking \ ˈkȯ-​kiŋ How to pronounce caulk (audio) \

Definition of caulk (Entry 2 of 3)

: material used to caulk


noun (2)

variant spelling of , calk entry 3

: a cleat on the shoe of a horse to prevent slipping also : a similar device worn on the sole of a shoe

Other Words from caulk


caulker noun

Examples of caulk in a Sentence

Verb He carefully caulked the area around the windows.
Recent Examples on the Web: Verb At a time when most other countries are finding ways to live with covid—including countries with previously strict covid rules, such as New Zealand and Singapore—Hong Kong is still clinging to its ambition to caulk the city firmly against the virus. Samanth Subramanian, Quartz, 21 Jan. 2022 One of Chapman-Henderson’s favorite tips is to caulk and brace roof ventilation soffit vents to reduce the amount of water blown into your attic during hurricane-force winds and rain. Washington Post, 4 Jan. 2022 Once your panels are up, caulk the seams to unify the panels. Sara Rodrigues, House Beautiful, 17 Mar. 2021 With a garden hose, inspect your bus’s windows for leaks, which happen when the exterior caulk around them ages and dries out or peels away, allowing rainwater to seep in. Will Sutherland, Popular Mechanics, 4 Dec. 2019 Check on the condition of your mechanicals and make sure your windows and doors are properly caulked. New York Times, 20 Mar. 2020 It’s time to finally get around to those home improvement projects that may have been piling up, like fixing leaky faucets or caulking cracks around the window. London Gibson, Indianapolis Star, 17 Apr. 2020 And while there are several ways to seal any drafty windows in your home, the best approach requires a two-pronged attack: caulking around the outside of the window and weather stripping the inside. Joseph Truini, Popular Mechanics, 13 Sep. 2019 Add caulking around the hearth and check the seal on the flue damper to make it as snug as possible., 30 Oct. 2019 Recent Examples on the Web: Noun Fletchall uses a nail gun to install the molding and fills the holes with caulk. Washington Post, 13 Oct. 2021 When a crude is heavy, those chains are long and enormous, giving the consistency of window putty or caulk. Robinson Meyer, The Atlantic, 16 Mar. 2022 Seal gaps and cracks with caulk or weather stripping to keep the cold air out in the winter and the hot air out in the summer. Kaylei Fear, Better Homes & Gardens, 15 Mar. 2022 Also check for cracks in caulk or loose sections of flashing around the chimney, vent pipes or skylights. Washington Post, 12 Nov. 2021 Silicone caulk is your home’s best friend for outdoor repairs, says Brock. Gregory Burnett, cleveland, 5 Mar. 2022 That means auto lubricants, your engine’s rubber gaskets, the ice cube trays in your freezer, and the caulk in your bathroom are all made from silicon. David Lumb, Popular Mechanics, 9 Dec. 2020 Windowsills: Seal any cracks around the window where rain is entering with caulk. Dan Diclerico, Good Housekeeping, 3 Feb. 2022 Seal leaks and gaps around your home with caulk, spray foam or weather-stripping, and check to make sure warm-air registers are not blocked by furniture or other objects around your house. Krista Johnson, The Courier-Journal, 2 Feb. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'caulk.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of caulk


15th century, in the meaning defined above

Noun (1)

1954, in the meaning defined above

History and Etymology for caulk


Middle English caulken, from Anglo-French cauker, calcher, chalcher to trample, from Latin calcare, from calc-, calx heel

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Time Traveler for caulk

Time Traveler

The first known use of caulk was in the 15th century

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Dictionary Entries Near caulk

cauline bundle



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Cite this Entry

“Caulk.” Dictionary, Merriam-Webster, Accessed 17 May. 2022.

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More Definitions for caulk


\ ˈkȯk How to pronounce caulk (audio) \
caulked; caulking

Kids Definition of caulk

 (Entry 1 of 2)

: to fill up a crack, seam, or joint so as to make it watertight


variants: also caulking \ ˈkȯ-​kiŋ \

Kids Definition of caulk (Entry 2 of 2)

: material used to fill up a crack, seam, or joint so as to make it watertight

More from Merriam-Webster on caulk

Thesaurus: All synonyms and antonyms for caulk

Nglish: Translation of caulk for Spanish Speakers


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