"salty, briny," 1510s, from Dutch brak "brackish," probably from Middle Dutch brak "worthless," a word also used in commercial trade and which also made its way into early Modern English.
Examples from the Web for brack
Well but, Judge Brack—it would show the most incredible lack of consideration for me.Hedda Gabler|Henrik Ibsen
Brack thanked him and said: "Goin' to ride any winners to-morrow, sir?"
Brack listened attentively; at first he hardly grasped the full meaning.
Brack gave an audible chuckle as he said: "Lor' love us, that'll just about bust him if it comes off."
"Well, Brack, I am glad you came," he said as he shook hands.