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sealant

SEE-luhnt /ˈsiː.lənt/

nounB2TOEFL

TechnicalTrade

A flexible substance applied to fill joints, gaps, or cracks on exterior surfaces to block water, air, or dust intrusion.

Unlike rigid glues, architectural sealants maintain elasticity to accommodate thermal expansion and structural shifting without tearing.

The story behind the word. Traces back to Latin 'sigillum' (a wax seal stamp used to prove an envelope was unopened). The term expanded from official wax seals that closed secret documents to synthetic compounds used to close architectural joints.

Word relationships

caulk: Caulk usually describes rigid acrylic compounds for interior trim, while sealant describes flexible elastomeric exterior compounds.

solvent: Solvents dissolve or break down bonded materials, whereas sealants fill gaps and seal joints together.

Commonly confused with

adhesive: Adhesives join materials under structural load; sealants fill voids to exclude air and water while permitting joint movement.

Word family

seal (verb/noun): To close tight against fluid or gas leakage.

Collocations

silicone sealant
polyurethane sealant
joint sealant
elastomeric sealant

Example sentences

"Applying silicone sealant around window frames and exterior trim prevents chilly winter drafts and rain intrusion." Home weatherization project
"The worker squeezed a uniform bead of polyurethane sealant into the expansion joint between exterior cladding panels." Modern wall system assembly

Memory hook

SEALANT SEALS leaks tight so water cannot seep into gaps. Gap-filling compound.

When not to use

Do not confuse sealant with structural adhesives; sealant's core purpose is sealing gaps rather than carrying heavy physical loads.

Fun facts

Aerospace sealants used on high-altitude commercial jetliners maintain full flexibility at temperatures ranging from -65°F to well over 300°F!