Etymology
From Middle English befilen, from Old English befȳlan (“to befoul, defile, make dirty”), from Proto-West Germanic *bifūlijan (“to make foul”), equivalent to be- + file. Cognate with Scots befile (“to befile”), West Frisian befûlje (“to dirty”), Dutch bevuilen (“to soil, dirty”), German Low German befulen (“to soil, pollute”). See also defile.