caulk

 
Pronunciation: /kɔːk/
(US also calk)

noun

[mass noun]
  • a waterproof filler and sealant, used in building work and repairs: use silicone caulk to ensure that you have an all-season moisture seal

verb

[with object]
  • seal (a gap or seam) with caulk: caulk all cracks between the trim and siding or masonry
  • make (a boat) watertight by stopping up any gaps in its hull: a garden must be cleared, boats caulked, and nets mended

Derivatives

caulker

noun

Origin:

late Middle English (in the sense 'copulate', used of birds): from Old Northern French cauquer, caukier, variant of cauchier 'tread, press with force', from Latin calcare 'tread', from calx, calc- 'heel'