quarantine

Where does the word "quarantine" come from? It comes from Italian quaranta, passing through Venetian Italian before entering English (1600s).

Quarantine’s story begins in Italian: quaranta meant “forty.” By medieval, the word had taken hold in Venetian Italian as quarantena. The forty-day isolation period required of ships arriving during the plague. It reached English by 1600s as quarantine. Venetian 'quaranta giorni', forty days, the isolation required of ships during plague in the 1300s–1400s. Today, quarantine means a period of isolation imposed to prevent the spread of disease.

1. Stage 1 · Italian · medieval quaranta "forty", meaning "forty".
2. Stage 2 · Venetian Italian · medieval quarantena "a forty-day isolation period", the forty-day isolation period required of ships arriving during the plague.
3. Stage 3 · English · 1600s quarantine "a period of enforced isolation to prevent disease spread", Venetian 'quaranta giorni', forty days, the isolation required of ships during plague in the 1300s–1400s.