BAC or BACK, noun 1. In navigation, a ferry-boat or praam. 2. In brewing, a large flat tub, or vessel, in which wort is cooled before boiling; hence called a cooler. 3. In distilleries, a vessel into which the liquor to be fermented is pumped, from the cooler, in order to be worked with the yeast.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI