seal
noun [ C ]
uk/siːl/ usan official mark on a document, sometimes made with wax, that shows that it is legal or has been officially approved:
The documents were marked with the official seal.
a thin piece of paper or plastic that covers the opening of a container and has to be broken before the contents can be used:
The seal on the bottle was broken.
something fixed around the edge of an opening to prevent liquid or gas flowing through it:
A video showed cracked seals and leaking water inside the coal mine.
under seal
LAW
if something is under seal, it cannot be seen, copied, or taken away:
His file is currently under seal.
See also
company seal
seal
verb [ T ]
uk/siːl/ usto make an agreement more certain or to approve it formally:
seal sth with sth The loans are typically sealed with handshakes.
to close an entrance or container so that nothing can enter or leave it:
The doors are sealed.
to cover a surface with a special liquid in order to protect it:
seal sth with sth The office floors were sealed with varnish.
to close a letter or parcel by sticking the edges together:
seal down sth Seal down the envelope.