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English definition of “seal”

seal

noun [C]     /siːl/
an 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
(Definition of seal noun from the Cambridge Business English Dictionary © Cambridge University Press)
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