Definitions of seal:

• noun:   any of numerous marine mammals that come on shore to breed; chiefly of cold regions
• noun:   a device incised to make an impression; used to secure a closing or to authenticate documents
• noun:   fastener that provides a tight and perfect closure
• noun:   a finishing coat applied to exclude moisture
• noun:   a stamp affixed to a document (as to attest to its authenticity or to seal it)

  Example: "The warrant bore the sheriff's seal"

• noun:   the pelt or fur (especially the underfur) of a seal

  Example: "A coat of seal"

• noun:   fastener consisting of a resinous composition that is plastic when warm; used for sealing documents and parcels and letters
• noun:   an indication of approved or superior status
• noun:   a member of a Naval Special Warfare unit who is trained for unconventional warfare

  Example: "SEAL is an acronym for Sea Air and Land"

• verb:   decide irrevocably

  Example: "Sealing dooms"

• verb:   hunt seals
• verb:   close with or as if with a seal

  Example: "She sealed the letter with hot wax"

• verb:   make tight; secure against leakage

  Example: "Seal the windows"

• verb:   affix a seal to

  Example: "Seal the letter"

• verb:   cover with varnish
• name:  A surname (common: 1 in 20000 families; popularity rank in the U.S.: #2728)