From Longman Dictionary of Contemporary Englishsealantseal‧ant /ˈsiːlənt/ noun [countable, uncountable] TDa substance that is put on the surface of something to protect it from air, water etc
Examples from the Corpus
sealant• Cracks should be repaired with a filler, and porous surfaces primed with a sealant or a diluted coat of masonry paint.• All necessary bolts and sealant were supplied by the manufacturer.• Clear out loose and damaged material and fill with exterior sealant, which will remain flexible 11 Check all brickwork pointing.• The body has been left unfinished, and only an oil sealant has been given to the wood to protect it.• It can be sealed with several coats of varnish or special sealant in humid areas like bathrooms or kitchens.• Termites are necessary to decompose old woody vegetation, but they were fond of eating the sealant around the windows.• The sealant would expand or contract by that amount as the building shifted.• So the wrong sealant was picked out of all the crevices and the correct, two-component mixture squeezed into place. 