Slade

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From Middle English slade(“low-lying ground, a valley; a flat grassy area, glade; hollows of clouds; a creek, stream; a channel”), from Old English slæd(“valley, glade”), from Proto-West Germanic *slad, from Proto-Germanic *sladą(“glen, valley”), of uncertain origin. Perhaps from Proto-Germanic *sladaną(“to glide, slip”) or Proto-Germanic *sladdaz(“to be slack, droop”). Compare Old Norse slóð(“track, trail”).

Unknown.