Where does “scumboard” come from?

scumboard (English) comes from English board, from English boardrider, from English rider, from Middle English ridere, from Middle English ryder, from Old English rīdere, from Old English rīdan, from Proto-West Germanic rīdan — to fit, to fix, to put together.

scumboard (English): A partition in a sewage tank etc. to block the passage of floating solids

Definitions

  1. A partition in a sewage tank etc. to block the passage of floating solids

Ancestry of “scumboard”, step by step

scumboard traces back through two separate lines of ancestry.

via English board

StepLanguageWordMeaning
1EnglishboardA relatively long, wide and thin piece of any...
2Englishboardridersurfer
3EnglishriderOne who rides, often on a horse or a motorcycle;...
4Middle EnglishridereAlternative form of ryder
5Middle EnglishryderA rider or equestrian; one who rides a horse; A...
6Old Englishrīdererider, knight
7Old Englishrīdanto ride
8Proto-West Germanicrīdanto ride
9Proto-Germanicrīdanąto ride
10Proto-Indo-Europeanrēydʰ-
11Proto-Indo-Europeanh₂er-to fit, to fix, to put together

via English scum

StepLanguageWordMeaning
1EnglishscumA layer of impurities that accumulates at the...
2Middle Englishscum
3Middle Dutchschūmefoam
4Old Dutch*scūm
5Frankishskūmfoam; froth, foam
6Proto-Germanicskūmazfilm; grime; scum; foam; froth; yeast
7Proto-Indo-European(s)kewH-to cover, bedeck; cover
Every word from Proto-Indo-European h₂er-Every word from Proto-Indo-European rēydʰ-Every word from Proto-Germanic rīdaną