n. & v.
n. 1 a piece of wax, lead, paper, etc., with a stamped design, attached to a document as a guarantee of authenticity. 2 a similar material attached to a receptacle, envelope, etc., affording security by having to be broken to allow access to the contents. 3 an engraved piece of metal, gemstone, etc., for stamping a design on a seal. 4 a a substance or device used to close an aperture or act as a fastening. b an amount of water standing in the trap of a drain to prevent foul air from rising. 5 an act or gesture or event regarded as a confirmation or guarantee. 6 a significant or prophetic mark (has the seal of death in his face). 7 a decorative adhesive stamp. 8 esp. Eccl. a vow of secrecy; an obligation to silence.
v.tr. 1 close securely or hermetically. 2 stamp or fasten with a seal. 3 fix a seal to. 4 certify as correct with a seal or stamp. 5 (often foll. by up) confine or fasten securely. 6 settle or decide (their fate is sealed). 7 (foll. by off) put barriers round (an area) to prevent entry and exit, esp. as a security measure. 8 apply a non-porous coating to (a surface) to make it impervious. Great Seal (in the UK) the seal in the charge of the Lord Chancellor or Lord Keeper used in sealing important State papers. one's lips are sealed one is obliged to keep a secret. sealed-beam (attrib.) designating a vehicle headlamp with a sealed unit consisting of the light source, reflector, and lens. sealed book see BOOK. sealed orders orders for procedure not to be opened before a specified time. sealing-wax a mixture of shellac and rosin with turpentine and pigment, softened by heating and used to make seals. seal ring a finger ring with a seal. seals of office (in the UK) those held during tenure esp. by the Lord Chancellor or a Secretary of State. set one's seal to (or on) authorize or confirm. sealable adj.
[ ME f. AF seal, OF seel f. L sigillum dimin. of signum SIGN ]