This term is often used by the people of New England, in speaking of the state of the roads, when they are covered with snow, and a thaw takes place. It is very common to hear people say, 'the roads are sloshy; it is very sloshy going,' &c. None of the English dictionaries have this word; but all of them, I believe, except Bailey's, have the term sludge and define it as Dr. Johnson does--'Mire, dirt mixed with water.' Grose has sludge in the same sense, as a provincial term, peculiar to the North of England. Marshall also has sludge among his provincialisms of the Midland counties, sluss among those of Norfolk, and slush among those of Yorkshire; and he defines them all nearly in the same words.--Pickering.
It sometimes happens that a fall of snow in the night time will cover the deep water where the feiths are, with snow and slush.--State, Leslie of Powis, 1803.