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English definition of “seal”

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seal

noun [C] uk   /siːl/ us  

seal noun [C] (ANIMAL)

B2 a large mammal that eats fish and lives partly in the sea and partly on land or ice
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seal noun [C] (COVERING)

something fixed around the edge of an opening to prevent liquid or gas flowing through it: Clean the seal on/around the fridge door regularly so that it remains airtight. a thin piece of material such as paper or plastic that covers the opening of a container and has to be broken in order to open the container and use the contents

seal noun [C] (MARK)

an official mark on a document, sometimes made with wax, that shows that it is legal or has been officially approved: The lawyer stamped the certificate with her seal.

seal

verb [T] uk   /siːl/ us  

seal verb [T] (COVERING)

C2 to close an entrance or container so that nothing can enter or leave it to cover a surface with a special liquid to protect it: This floor has just been sealed (with varnish), so don't walk on it!C2 to close a letter or parcel by sticking the edges together: Seal the package (up) with sticky tape. He sealed (down) the envelope and put a stamp on it.
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seal verb [T] (MARK)

to make an agreement more certain or to approve it formally: The two leaders sealed their agreement with a handshake.
(Definition of seal from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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