'nonedematous' originates from Modern English, specifically the prefix 'non-' (from Latin 'non') meaning 'not' combined with 'edematous,' which ultimately comes from Greek 'oidēma' via medical Latin, where 'oidēma' meant 'swelling'.

'edematous' developed from the noun 'edema' (from Greek 'oidēma') entering English through Latin/medical usage; the adjective 'nonedematous' was formed later by adding the productive English prefix 'non-' to negate that adjective, producing the modern English form 'nonedematous'.

Initially 'oidēma' meant 'a swelling'; over time 'edematous' came to mean 'characterized by swelling' and 'nonedematous' the straightforward negation meaning 'not characterized by swelling'.