Swiss (n.)

"native or inhabitant of Switzerland," 1510s, from French Suisse, from Middle High German Suizer, from Suiz "Switzerland" (see Switzerland). Alternative Switzer (1570s) "a Swiss" now is archaic (compare German Schweizer). English also used Swisser.

As an adjective from 1520s, "of or belonging to Switzerland or the Swiss." Swiss Guards, in reference to a mercenary troop protecting a sovereign, is by 1700. Swiss banks were notable by 1949 for assuring anonymity and security. Swiss cheese is attested from 1808; colloquially as a type of something "full of holes," by 1924.