The Collaborative International Dictionary of English v.0.48:
Brack \Brack\, n. [D. brak, adj., salt; cf. LG. wrak refuse, G.
   brack.]
   Salt or brackish water. [Obs.] --Drayton.
   [1913 Webster]
The Collaborative International Dictionary of English v.0.48:
Brack \Brack\ (br[a^]k), n. [Cf.D. braak, Dan. br[ae]k, a
   breaking, Sw. & Icel. brak a crackling, creaking. Cf.
   Breach.]
   An opening caused by the parting of any solid body; a crack
   or breach; a flaw.
   [1913 Webster]
         Stain or brack in her sweet reputation.  --J. Fletcher.
   [1913 Webster]