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c.1300, slete, either from an unrecorded Old English *slete, *slyte, related to Middle High German sloz, Middle Low German sloten (plural) "hail," from Proto-Germanic *slautjan- (cf. dialectal Norwegian slutr, Danish slud, Swedish sloud "sleet"), from root *slaut-.
early 14c., from sleet (n.). Related: Sleeted; sleeting.
Precipitation that falls to earth in the form of frozen or partially frozen raindrops, often when the temperature is near the freezing point. Sleet usually leaves the cloud in the form of snow that melts as it passes through warm layers of air during its descent. The raindrops and partially melted snowflakes then freeze in the colder layers nearer the earth before striking the ground as pellets of ice, which usually bounce. By contrast,hail forms by the accumulation of layers of ice on the hailstone as it moves up and down in the cloud, and hailstones can become much larger than sleet pellets. The word sleet is also used informally to describe a mixture of snow, sleet, and rain.
globular, generally transparent ice pellets that have diameters of 5 mm (0.2 inch) or less and that form as a result of the freezing of raindrops or the freezing of mostly melted snowflakes. Larger particles are called hailstones (see hail). Sleet may occur when a warm layer of air lies above a below-freezing layer of air at the Earth's surface. In Great Britain and in some parts of the United States, a mixture of rain and snow is called sleet, and the term has sometimes been used to identify the clear ice on objects that is more correctly known as glaze.