a device or substance that is used to join two things together so as to prevent them from coming apart or to prevent anything from passing between them.
blue smoke from the exhaust suggests worn valve seals
a piece of wax, lead, or other material with an individual design stamped into it, attached to a document to show that it has come from the person who claims to have issued it.
He replied, handing her a letter with a navy blue wax seal .
a thing regarded as a confirmation or guarantee of something.
the International Monetary Fund is likely to give a seal of approval to the Mexican plan
the obligation on a priest not to divulge anything said during confession.
I was told under the seal