caulk

American  

[kawk] / kɔk /

Or calk

verb (used with object)

1. to fill or close seams or crevices of (a tank, window, etc.) in order to make watertight, airtight, etc.

2. to make (a vessel) watertight by filling the seams between the planks with oakum or other material driven snug.

3. to fill or close (a seam, joint, etc.), as in a boat.

4. to drive the edges of (plating) together to prevent leakage.

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noun

1. Also caulking a material or substance used for caulking.

caulk British  

/ kɔːk /

verb

1. to stop up (cracks, crevices, etc) with a filler

2. nautical to pack (the seams) between the planks of the bottom of (a vessel) with waterproof material to prevent leakage

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Other Word Forms

• caulker noun

Etymology

Origin of caulk

First recorded in 1350–1400; from Latin calcāre “to trample, tread on” (verb derivative of calx “heel”), conflated with Middle English cauken, from Old French cauquer “to trample,” from Latin calcāre, as above

Example Sentences

Radiocarbon testing of the cordage and caulk indicates the boat was built between the 4th and 3rd centuries BCE.

From Science Daily • Feb. 16, 2026

To answer those questions, the research team examined previously unstudied materials recovered with the vessel, including cordage and waterproofing caulk.

From Science Daily • Feb. 16, 2026

Seal these rifts with puttylike rope caulk and begin shrink-wrapping before winter’s icy grip takes hold.

From Seattle Times • Oct. 20, 2023

Expanding foam sealant, weather-stripping and caulk are excellent solutions for many such problems.

From Seattle Times • Apr. 19, 2023

The exterior sustained some damage, so they’ll pressure-wash it, sand and caulk it, and repaint every wall and window.

From "Zeitoun" by Dave Eggers

Related Words

• block
• shut
• shutter