coomb
A tub or vat, especially used in brewing.
An old English measure of corn (e.g., wheat), equal to half a quarter or 4 bushels.
It was equal to half a quarter, i.e. is identical with the coomb of the eastern counties.
Where it comes from
From Middle English *coumb, *comb, *cumb (> Scots cumb, coom (“tub, cistern”)), from Old English cumb (“a vessel; a liquid measure”), from Proto-West Germanic *kumb, from Proto-Germanic *kumbaz (“bowl, vessel”), probably from Proto-Indo-European *gew- (“to bend, curve”). Cognate with Dutch kom (“basin, bowl”), German Kumpf (“bowl”).
Adapted from the Wiktionary entry coomb (CC BY-SA 4.0).