Where does “fill-dyke” come from?

fill-dyke (English) comes from English Fill, from Middle English fillen, from Old English fyllan, from Proto-West Germanic *fullijan, from Proto-Germanic fullijaną, from Proto-Germanic fullaz, from Proto-Indo-European pl̥h₁nós, from Proto-Indo-European pleh₁- — to fill.

Ancestry of “fill-dyke”, step by step

fill-dyke traces back through two separate lines of ancestry.

via English Fill

StepLanguageWordMeaning
1EnglishFillTo make full
2Middle Englishfillento fill
3Old Englishfyllanto fill; Alternative form of fiellan
4Proto-West Germanic*fullijanto fill
5Proto-Germanicfullijanąto fill, to make full
6Proto-Germanicfullazfull; the whole, the entire
7Proto-Indo-Europeanpl̥h₁nósfull
8Proto-Indo-Europeanpleh₁-to fill

via English dyke

StepLanguageWordMeaning
1EnglishdykeA long, narrow hollow dug from the ground to...
2Dutchdijkdike, levee
3Middle Dutchdijcditch; dam
4Old Dutchdiic
5Frankish*dīk
6Proto-Germanicdīkazpool, puddle
7Proto-Indo-Europeandʰēygʷ-to stick into, pierce
Every word from Proto-Indo-European pleh₁-Every word from Proto-Indo-European pl̥h₁nósEvery word from Proto-Germanic fullaz