\ 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 calking (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

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Other Words from caulk


caulker noun

Examples of caulk in a Sentence


He carefully caulked the area around the windows.

Recent Examples on the Web: Verb

For electrical outlets, caulk around the box, or, even better, buy cover plates with gaskets. Henry Gifford, Popular Mechanics, "Your House Is Bleeding You Dry. Here Are 9 Steps To Save You Money.," 8 Aug. 2018 Sweet-smelling resin, which could have been used for incense or for caulking ships, was also found. James Rogers, Fox News, "Shipwreck mystery solved thanks to 800-year-old 'Made in China' label," 16 May 2018 Also, caulking was insufficient to hold back water in certain areas, according to the report. Mary Shanklin,, "UCF stadium has failing areas, report shows; some fixed, school says," 13 Oct. 2017 Talk about a pain in the ass – caulking windows is boring. Michelle R. Martinelli, For The Win, "Dale Jr. and Amy Earnhardt's home improvement series is finally going to be on TV," 25 Apr. 2018 The art panels affixed to the concrete-along with metal roofs and end panels-were seamlessly sealed, caulked, and screwed into place. Jeff Huebner, Chicago Reader, "What ever happened to the King Memorial Mural at 43rd and Langley?," 24 Apr. 2018 Plan Ahead: Don't start caulking at a random corner or end point. Roy Berendsohn, Popular Mechanics, "How to Caulk Your Bathtub," 20 Feb. 2018 If the nest is inside walls or inaccessible, cut off the paths ants follow by caulking cracks and crevices., "The annual home pest invasion is coming; here are tips to do it yourself or hire an exterminator," 28 Mar. 2018 For an enclosed tub, start caulking at one corner and then reverse the bead at the far end. Roy Berendsohn, Popular Mechanics, "How to Caulk Your Bathtub," 20 Feb. 2018

Recent Examples on the Web: Noun

Use a silicone caulk designed for kitchens and bathrooms, in a color that coordinates with your design. Joseph Truini, Popular Mechanics, "Your Quick and Dirty Guide to Tiling a Kitchen Backsplash," 26 Apr. 2019 For lower-lift solutions, the DOE offers instructions for a variety of DIY weatherization techniques, like how to air seal leaks with caulk and how to properly cover attic stairs. Barbara Eldredge, Curbed, "How to save on utility bills," 25 Jan. 2019 In general, look for caulks made with mold-free technology that adhere to common surfaces. The Good Housekeeping Institute, Good Housekeeping, "How to Draft-Proof Your Home for a Lower Heating Bill," 20 Nov. 2018 Add or replace worn weather stripping or caulk anywhere air is leaking in. Paul F.p. Pogue, The Seattle Times, "How to find and stop the drafts that are stealing your home’s energy," 1 Oct. 2018 Use weatherstripping or caulk to seal them up, or consider replacing the windows or doors if the problem is severe enough. Taylor Mead, House Beautiful, "What You Need To Do To Your Home Before Winter Starts," 19 Sep. 2018 The caulking gun: Another culprit that leads to plenty of bad caulking jobs is the $1.99 caulk gun. Roy Berendsohn, Popular Mechanics, "How to Caulk Your Bathtub," 20 Feb. 2018 Apply grout sealer, and reapply waterproof silicone caulk, if needed. The Editors Of House Beautiful, House Beautiful, "How to Grout Tile," 11 Feb. 2015 First of all: Grout is the mortar that fills the gaps between tile; caulk is the waterproof sealant used to seal gaps or seams around tubs, sinks, and toilets, especially in the shower or around the tub. Jolie Kerr, SELF, "How to Clean Your Bathroom In 10 Minutes," 19 Apr. 2018

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.

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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

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

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More Definitions for caulk



English Language Learners Definition of caulk

: to fill the cracks or holes in (something) with a substance that keeps out water


\ 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

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More from Merriam-Webster on caulk

Rhyming Dictionary: Words that rhyme with caulk

Spanish Central: Translation of caulk

Nglish: Translation of caulk for Spanish Speakers

Comments on caulk

What made you want to look up caulk? Please tell us where you read or heard it (including the quote, if possible).


incapable of being surmounted or overcome

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