sealant
/ˈsiːlənt/
noun
- A substance used to close or fill a gap, joint, or surface to prevent air, water, or other substances from passing through.
- You should use a sealant on the wooden deck to protect it from rain.
- The dentist recommended a fluoride sealant for my child's teeth.
- The plumber applied silicone sealant around the bathtub to stop leaks.
Synonyms