What does "seal" mean?

Seal: An engraved or inscribed stamp, used for marking an impression in wax or other soft substance, to be attached to a document, or otherwise used by way of authentication or security.

Additional senses

  1. 2.Wax, wafer, or other tenacious substance, set to an instrument, and impressed or stamped with a seal; as, to give a deed under hand and seal. Till thou canst rail the seal from off my bond Thou but offend;st thy lungs to speak so loud. Shak.
  2. 3.That which seals or fastens; esp., the wax or wafer placed on a letter or other closed paper, etc., to fasten it.
  3. 4.That which confirms, ratifies, or makes stable; that which authenticates; that which secures; assurance. "under the seal of silence." Milton. Like a red seal is the setting sun On the good and the evil men have done. Lonfellow.
  4. 5.An arrangement for preventing the entrance or return of gas or air into a pipe, by which the open end of the pipe dips beneath the surface of water or other liquid, or a deep bend or sag in the pipe is filled with the liquid; a draintrap. Great seal. See under Great. -- Privy seal. See under Privy, a. -- Seal lock, a lock in which the keyhole is covered by a seal in such a way that the lock can not be opened without rupturing the seal. Seal manual. See under Manual, a. -- Seal ring, a ring having a seal engraved on it, or ornamented with a device resembling a seal; a signet ring. Shak.
  5. 6.To set or affix a seal to; hence, to authenticate; to confirm; to ratify; to establish; as, to seal a deed. And with my hand I seal my true heart's love. Shak.
  6. 7.To mark with a stamp, as an evidence of standard exactness, legal size, or merchantable quality; as, to seal weights and measures; to seal silverware.
  7. 8.To fasten with a seal; to attach together with a wafer, wax, or other substance causing adhesion; as, to seal a letter.
  8. 9.Hence, to shut close; to keep close; to make fast; to keep secure or secret. Seal up your lips, and give no words but "mum". Shak.
  9. 10.To fix, as a piece of iron in a wall, with cement, plaster, or the like. Gwilt.
  10. 11.To close by means of a seal; as, to seal a drainpipe with water. See 2d Seal, 5.
  11. 12.Among the Mormons, to confirm or set apart as a second or additional wife. [Utah, U.S.] If a man once married desires a second helpmate . . . she is sealed to him under the solemn sanction of the church. H. Stansbury.
  12. 13.To affix one's seal, or a seal. [Obs.] I will seal unto this bond. Shak.

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