'Sleet' is Proto-Germanic for 'striking precipitation' — related to German 'Schlosse' (hailstone).
A form of precipitation consisting of ice pellets formed when raindrops freeze before reaching the ground, or a mixture of rain and snow.
From Middle English slete, from a Proto-Germanic base *slautaz or *sleutaz, cognate with Middle Low German sloten (to hail), Middle High German sloze (hailstone), and Dutch sleet. Ultimately from PIE *sleu- (to be slack, to slide), related to *slei- (slime, slimy), reflecting how sleet — a mixture of rain and snow or ice pellets — slides and smears when it strikes. Attested in Middle English from the 14th century and stable in form ever since. The percussive quality of sleet striking a surface is encoded in the root's association with striking: the sliding, slushy texture and the smacking impact