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noun \ˈsēl\

Definition of seal

plural seals also seal

  1. 1 :  any of numerous carnivorous marine mammals (families Phocidae and Otariidae) that live chiefly in cold regions and have limbs modified into webbed flippers adapted primarily to swimming; especially :  a fur seal or hair seal as opposed to a sea lion

  2. 2a :  the pelt of a fur sealb :  leather made from the skin of a seal

  3. 3 :  a dark brown

Origin of seal

Middle English sele, from Old English seolh; akin to Old High German selah seal

First Known Use: before 12th century

Other Mammals Terms



intransitive verb

Definition of seal

  1. :  to hunt seals


First Known Use of seal


Other Hunting and Fishing Terms




Definition of seal

  1. 1a :  something that confirms, ratifies, or makes secure :  guarantee, assuranceb (1) :  a device with a cut or raised emblem, symbol, or word used especially to certify a signature or authenticate a document (2) :  a medallion or ring face bearing such a device incised so that it can be impressed on wax or moist clay; also :  a piece of wax or a wafer bearing such an impressionc :  an impression, device, or mark given the effect of a common-law seal by statute law or by American local custom recognized by judicial decisiond :  a usually ornamental adhesive stamp that may be used to close a letter or package; especially :  one given in a fund-raising campaign

  2. 2a :  something that secures (as a wax seal on a document)b :  a closure that must be broken to be opened and that thus reveals tamperingc (1) :  a tight and perfect closure (as against the passage of gas or water) (2) :  a device to prevent the passage or return of gas or air into a pipe or container

  3. 3 :  a seal that is a symbol or mark of office

under seal
  1. :  with an authenticating seal affixed

Origin of seal

Middle English sele, seel, from Anglo-French seal, sel, from Latin sigillum seal, from diminutive of signum sign, seal — more at sign

First Known Use: 13th century



transitive verb

Definition of seal

  1. 1a :  to confirm or make secure by or as if by a seal <seal the deal>b :  to solemnize for eternity (as a marriage) by a Mormon rite

  2. 2a :  to set or affix an authenticating seal to; also :  authenticate, ratifyb :  to mark with a stamp or seal usually as an evidence of standard exactness, legal size, weight, or capacity, or merchantable quality

  3. 3a :  to fasten with or as if with a seal to prevent tamperingb :  to close or make secure against access, leakage, or passage by a fastening or coatingc :  to fix in position or close breaks in with a filling (as of plaster)

  4. 4 :  to determine irrevocably or indisputably <that answer sealed our fate>

14th Century

First Known Use of seal

14th century



Definition of SEAL

  1. sea, air, land (team)

Medical Dictionary


transitive verb \ˈsēl\

Medical Definition of seal

  1. :  to apply dental sealant to <the teeth to be sealed are surrounded by cotton rolls and dried thoroughly—J. W. Friedman>

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February 10, 2016

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