D defs.my
Entry 2 senses Webster, 1913

Unseal

/(ŭn*sēl")/ · Un·seal · IPA /ʌnˈsiːl/
01 v. t. To break or remove the seal of; to open, as what is sealed; as, to unseal a letter.
  1. 1.
    To break or remove the seal of; to open, as what is sealed; as, to unseal a letter.
    “Unable to unseal his lips beyond the width of a quarter of an inch.” Sir W. Scott.
  2. 2.
    To disclose, as a secret.[Obs.]