The Collaborative International Dictionary of English v.0.48:

Stegnotic \Steg*no"tic\, a. [Gr. stegnwtiko`s, fr. stegnoy^n to
   cover, to make costive, fr. stegno`s, stegano`s, covered,
   closed.] (Med.)
   Tending to render costive, or to diminish excretions or
   discharges generally. -- n. A stegnotic medicine; an
   astringent.
   [1913 Webster]