From Greek 'austēros' (dry, harsh, astringent) — originally a taste description for puckering, unripe fruit — the word traveled through Latin and French to English, extending from physical dryness to moral severity to economic belt-tightening.
Sternness or severity of manner or attitude; enforced or extreme economy, especially in public spending
Austerity entered English in the 14th century from Old French 'austerité,' from Latin 'austēritās' (severity, harshness), derived from 'austērus' (harsh, severe, dry). Latin borrowed this directly from Greek 'austēros' (αὐστηρός), which originally described a specific taste sensation: the dry, astringent, mouth-puckering quality of unripe fruit or certain wines. The Greek word derives from 'auein' (to dry
Greek 'austēros' was originally a wine-tasting term describing dry, astringent wine that puckered your mouth. The jump from 'this wine is harsh and dry' to 'this government budget is harsh and dry' took about 2,400 years but followed a straight metaphorical line — dryness as severity, severity as deprivation.