seal

Multiple Entries:
  seal    SEAL  

Concise Oxford English Dictionary © 2008 Oxford University Press:
seal1

▶noun

• 1 a device or substance used to join two things together or render something impervious.

  ■ the state or fact of being joined or rendered impervious with a seal.

• 2 a piece of wax, lead, etc. with an individual design stamped into it, attached to a document as a guarantee of authenticity.

  ■ a design embossed in paper for this purpose.

  ■ an engraved device used for stamping a seal.

  ■ a decorative adhesive stamp.

• 3 a confirmation or guarantee: a seal of approval.

• 4 (the seal or the seal of the confessional) the obligation on a priest not to divulge anything said during confession.

• 5 the water standing in the trap of a drain to prevent foul air from rising.

▶verb

• 1 fasten or close securely.

  ■ (seal something off) isolate an area by preventing or monitoring access to and from it.

• 2 apply a non-porous coating to (a surface) to make it impervious.

• 3 conclude, establish, or secure definitively: victory was sealed.

• 4 authenticate (a document) with a seal.

– phrases
my lips are sealed I will not discuss or reveal a secret.
put (or set) the seal on finally confirm or conclude.
set (or put) one's seal to (or on) mark with one's distinctive character.

– derivatives
sealable adjective.

– origin ME: from OFr. seel (n.), seeler (v.), from L. sigillum ‘small picture’, dimin. of signum ‘a sign’.

Concise Oxford English Dictionary © 2008 Oxford University Press:
seal2

▶noun a fish-eating aquatic mammal with a streamlined body and feet developed as flippers. [Families Phocidae (the true seals) and Otariidae (eared seals): many species.] ▶verb (usu. as noun sealing) hunt for seals.

– origin OE seolh, of Gmc origin.

Concise Oxford English Dictionary © 2008 Oxford University Press:
SEAL /siːl/ (also Seal)

▶noun a member of an elite force within the US Navy, specializing in guerrilla warfare and counter-insurgency.

– origin 1960s: abbrev. of ‘sea, air, land (team)’.