The plural of cul-de-sac is culs-de-sac

It sounds so simple, and yet it is true - “Culs-de-sac” is the plural of “Cul-de-sac”, and it makes perfect sense. A cul-de-sac is the round end of a street, and the word comes from the French, literally translating into English as “bottom of the sack” due to how the rounded end of a street looks. While “cul-de-sac” is the singular form, even a single one is often called a culs-de-sac.