1773 (as St. A Claus, in "New York Gazette"), American English, from dialectal Dutch Sante Klaas, from Middle Dutch Sinter Niklaas "Saint Nicholas," bishop of Asia Minor who became a patron saint for children. Now a worldwide phenomenon (Japanese santakurosu). Father Christmas is attested from 1650s.
sans-culotte
sansei
Sanskrit
sans-serif
Santa
Santa Claus
santeria
sap
sapid
sapience
sapient