branch water

WordReference Random House Unabridged Dictionary of American English © 2025

branch′ wa′ter, 

1. water in or from a branch, creek, stream, etc.;
   pure, natural water.
2. Dialect Terms, Wine Also called branch. [Chiefly South Midland and Southern U.S.] (in a drink, highball, etc.) plain water as distinguished from soda water, ginger ale, or the like;
   ordinary water.
• 1840–50