Where does “flannelboard” come from?

flannelboard (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.

Ancestry of “flannelboard”, step by step

flannelboard 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 flannel

StepLanguageWordMeaning
1EnglishflannelA soft cloth material woven from wool, possibly...
2Middle Englishflaunneol
3Old Frenchflanelle
4Old Frenchflaine
5Proto-Celticwlānos
6Proto-Celticwlanāwool
7Proto-Indo-Europeanh₂wĺ̥h₁neh₂wool
8Proto-Indo-European-nósCreates verbal adjectives from roots
Every word from Proto-Indo-European h₂er-Every word from Proto-Indo-European rēydʰ-Every word from Proto-Germanic rīdaną