seal

(noun) fastener consisting of a resinous composition that is plastic when warm; used for sealing documents and parcels and letters. Synonyms: sealing wax.

(noun) a device incised to make an impression; used to secure a closing or to authenticate documents. Synonyms: stamp.

(noun) the pelt or fur (especially the underfur) of a seal. Synonyms: sealskin. Examples: "A coat of seal."

(noun) a member of a Naval Special Warfare unit who is trained for unconventional warfare. Synonyms: Navy SEAL, SEAL. Examples: "Seal is an acronym for sea air and land."

(noun) a stamp affixed to a document (as to attest to its authenticity or to seal it). Examples: "The warrant bore the sheriff's seal."

(noun) an indication of approved or superior status. Synonyms: cachet, seal of approval.

(noun) a finishing coat applied to exclude moisture.

(noun) fastener that provides a tight and perfect closure.

(noun) any of numerous marine mammals that come on shore to breed; chiefly of cold regions.

(verb) make tight; secure against leakage. Synonyms: seal off. Examples: "Seal the windows."

(verb) close with or as if with a seal. Examples: "She sealed the letter with hot wax."

(verb) decide irrevocably. Examples: "Sealing dooms."

(verb) affix a seal to. Examples: "Seal the letter."

(verb) cover with varnish. Synonyms: varnish.

(verb) hunt seals.