prudish

the word 'prudish' is formed from the noun 'prude', which entered english from old french in the early 18th century, itself likely a back-formation from the feminine form of the old french adjective 'prud', meaning 'good, virtuous, wise'. this old french term finds its origin in the latin 'prōdesse', meaning 'to be of advantage', from 'prōd-', a variant of 'prō-' (for) + 'esse' (to be). the suffix '-ish', of germanic origin, is added to convey the sense of 'having the characteristics of' or 'tending toward'. thus, the literal construction 'like a prude' evolved into the modern abstract meaning, describing someone who is overly or affectedly proper and modest.

Structure: prud(e) + ish prud(e) (from middle english 'prude', from old french, meaning 'good, virtuous, modest') + ish (from old english '-isc', an adjective-forming suffix meaning 'having the qualities of' or 'somewhat')