sealant
/ˈsiːlənt
/noun [mass noun]
Material used for sealing something so as to make it airtight or watertight: blobs of silicone sealant [count noun]: use a flexible mastic sealant...
- The sealant made it airtight without pinching his nasal passage.
- Water putty, epoxies, construction glue and silicone sealants can cause irreversible damage to objects, he warned.
- I'll pull the assembly apart (hopefully I can just cut that sealant stuff off) and fill the hole with more sealant.