noun (1)
\ˈsēl \
plural seals also seal

Definition of seal 

(Entry 1 of 5)

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

2a : the pelt of a fur seal

b : leather made from the skin of a seal

3 : a dark brown


verb (1)
sealed; sealing; seals

Definition of seal (Entry 2 of 5)


noun (2)

Definition of seal (Entry 3 of 5)

1a : something that confirms, ratifies, or makes secure : guarantee, assurance

b(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 impression

c : an impression, device, or mark given the effect of a common-law seal by statute law or by American local custom recognized by judicial decision

d : a usually ornamental adhesive stamp that may be used to close a letter or package especially : one given in a fund-raising campaign

2a : something that secures (such as a wax seal on a document)

b : a closure that must be broken to be opened and that thus reveals tampering

c(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 : a seal that is a symbol or mark of office

under seal

: with an authenticating seal affixed


verb (2)
sealed; sealing; seals

Definition of seal (Entry 4 of 5)

transitive verb

1a : to confirm or make secure by or as if by a seal seal the deal

b : to solemnize (something, such as a marriage) for eternity by a Mormon rite

2a : to set or affix an authenticating seal to also : authenticate, ratify

b : to mark with a stamp or seal usually as an evidence of standard exactness, legal size, weight, or capacity, or merchantable quality

3a : to fasten with or as if with a seal to prevent tampering

b : to close or make secure against access, leakage, or passage by a fastening or coating

c : to fix in position or close breaks in with a filling (as of plaster)

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

\ˈsēl \

Definition of SEAL (Entry 5 of 5)

sea, air, land (team)

First Known Use of seal

Noun (1)

before the 12th century, in the meaning defined at sense 1

Verb (1)

1828, in the meaning defined above

Noun (2)

13th century, in the meaning defined at sense 1a

Verb (2)

14th century, in the meaning defined at sense 1a

History and Etymology for seal

Noun (1)

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

Noun (2)

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


Old French seel, from Latin sigillum, from diminutive of signum mark, sign

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Learn More about seal

Dictionary Entries near seal


sea king

sea kittie




sea lace

Statistics for seal

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Time Traveler for seal

The first known use of seal was before the 12th century

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More Definitions for seal


\ˈsēl \

Kids Definition of seal

 (Entry 1 of 3)

1 : a sea mammal that swims with flippers, lives mostly in cold regions, bears young on land, feeds on fish and other sea animals (as squid), and is sometimes hunted for its fur, hide, or oil

2 : the soft fur of a seal



Kids Definition of seal (Entry 2 of 3)

1 : something that closes tightly The seal on the package is broken.

2 : the condition of having a tight seal Caulk gives the window a seal.

3 : an official mark stamped or pressed on something She … stamped her own official seal beside his signature.— Lois Lowry, The Giver

4 : a device with a cut or raised design or figure that can be stamped or pressed into wax or paper

5 : a stamp that may be used to close a letter or package Christmas seals

6 : something (as a pledge) that makes safe or secure The deal was made under seal of secrecy.


sealed; sealing

Kids Definition of seal (Entry 3 of 3)

1 : to close tightly or completely to prevent anyone or anything from moving in or out

2 : to put an official mark on

Other Words from seal

sealer noun
\ˈsēl \

Medical Definition of seal 

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



Legal Definition of seal 

(Entry 1 of 2)

: a device (as an emblem, symbol, or word) used to identify or replace a signature and to authenticate (as at common law) written matter — see also contract under seal at contract

under seal

: with an authenticating seal affixed

Legal Definition of seal (Entry 2 of 2)

1 : to authenticate or approve by or as if by a seal

2 : to close off (as records) from public access

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a state of commotion or excitement

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