Entry 1 sense Webster, 1913 Brackish /brăk'-ĭsh/ · Brack·ish · IPA /ˈbɹækɪʃ/ 01 a. Saltish, or salt in a moderate degree, as water in saline soil. 1. Saltish, or salt in a moderate degree, as water in saline soil. “Springs in deserts found seem sweet, all brackish though they be.” — Byron.