CREVASSE (Fr.), a fissure in a glacier, may be transverse or longitudinal, brought about by tension due to unequal rates of movement, the central part generally moving faster than the margins, and (or) movement over an uneven surface. Irregular pinnacles of ice between crevasses of great magnitude on steep slopes are known as seracs (see GLACIER). The word crevasse is also applied to wide cracks in the raised banks of rivers and canals, e.g., in the levees of the Mississippi.