Origin: ME < OE leathor, washing soda or soap, akin to ON lauthr, washing soda, foam < IE *loutro- < base *lou-, to lave
See lather in American Heritage Dictionary 4
Origin: Probably from Middle English latheren, to wash or soak clothes
Origin: , from Old English lēthran, to cover with lather; see leu(ə)- in Indo-European roots.
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