Where does “yellowbrush” come from?

yellowbrush (English) comes from English Brush, from Middle English brusshe, from Old French broisse, from Vulgar Latin brustia, from Icelandic bursti, from Proto-Germanic burstiz, from Proto-Germanic bʰurstís, from Proto-Indo-European bʰr̥s-tí-s — top, tip, point.

Ancestry of “yellowbrush”, step by step

yellowbrush traces back through two separate lines of ancestry.

via English Brush

StepLanguageWordMeaning
1EnglishBrushAn implement consisting of multiple more or less flexible bristles or other filaments attached to a handle, used for any of various purposes including cleaning, painting, and arranging hair
2Middle Englishbrusshe
3Old Frenchbroisse
4Vulgar Latinbrustia
5Icelandicburstibrush
6Proto-Germanicburstizbristle
7Proto-Germanicbʰurstís
8Proto-Indo-Europeanbʰr̥s-tí-s
9Proto-Indo-Europeanbʰers-top, tip, point

via English yellow

StepLanguageWordMeaning
1EnglishyellowHaving yellow as its color; Lacking courage;...
2Middle Englishyelowyellow, yellowish, gold; yellow-coloured;...
3Old Englishġeoluyellow
4Proto-West Germanicgeluyellow
5Proto-Germanicgelwazyellow
6Proto-Indo-Europeanǵʰelh₃wósyellow, green
7Proto-Indo-Europeanǵʰelh₃-to flourish; green, yellow
Every word from Proto-Indo-European bʰers-Every word from Proto-Indo-European bʰr̥s-tí-sEvery word from Proto-Germanic bʰurstís
yellowbrush — Etymology, Origin & Word History | Etymology Explorer