The Collaborative International Dictionary
Bay salt
Bay salt \Bay" salt`\
Salt which has been obtained from sea water, by evaporation
in shallow pits or basins, by the heat of the sun; the large
crystalline salt of commerce.
--Bacon. Ure.
Wiktionary
bay salt
n. salt obtained from seawater by evaporation in shallow pits or basins, by the heat of the sun.