vi to affix one's seal, or a seal.
2. seal ·noun any aquatic carnivorous mammal of the families phocidae and otariidae.
3. seal ·vt to fix, as a piece of iron in a wall, with cement, plaster, or the like.
4. seal ·vt among the mormons, to confirm or set apart as a second or additional wife.
5. seal ·vt hence, to shut close; to keep close; to make fast; to keep secure or secret.
6. seal ·vt to close by means of a seal; as, to seal a drainpipe with water. ·see 2d seal, 5.
7. seal ·noun that which confirms, ratifies, or makes stable; that which authenticates; that which secures; assurance.
8. seal ·noun that which seals or fastens; ·esp., the wax or wafer placed on a letter or other closed paper, ·etc., to fasten it.
9. seal ·vt to fasten with a seal; to attach together with a wafer, wax, or other substance causing adhesion; as, to seal a letter.
10. seal ·noun 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.
11. seal ·vt 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.
12. seal ·vt to set or affix a seal to; hence, to authenticate; to confirm; to ratify; to establish; as, to seal a deed.
13. seal ·noun 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.
14. seal ·noun 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.