Definitions for "Frazil ice"
a slushy mush of ice spikelets formed by freezing in turbulent waters NRBS - Home Table of Contents
Fine, small needlelike structures or thin, flat, circular plates of ice suspended in water. In rivers and lakes it is formed in supercooled, turbulent water.
Stream ice with the consistency of slush, formed when small ice crystals develop in super-cooled stream water as air temperatures drop below freezing. These ice crystals join and are pressed together by newer crystals as they form. ( frasil)