Where does “pea flour” come from?

pea flour (English) comes from English pea, from English pease, from Middle English pese, from Old English pise, from Late Latin pisa, from Latin pīsum, from Ancient Greek πίσον, from Ancient Greek πίσος — pea, pease, seed of "Pisum sativum".

Ancestry of “pea flour”, step by step

pea flour traces back through two separate lines of ancestry.

via English pea

StepLanguageWordMeaning
1EnglishpeaAny of certain plants of the family Fabaceae: Pisum sativum and others
2EnglishpeaseTo make peace between (conflicting people, states etc.); to reconcile
3Middle EnglishpeseA pea; The leguminous plant Pisum sativum;...
4Old Englishpisepea
5Late Latinpisanominative plural of pisum; accusative plural of...
6Latinpīsumpea, pease
7Ancient GreekπίσονQuoted by comic poet Alexis; pea, pease, seed of...
8Ancient Greekπίσοςpea, pease, seed of "Pisum sativum"

via English flour

StepLanguageWordMeaning
1EnglishflourPowder obtained by grinding or milling cereal...
Every word from Ancient Greek πίσος