What is "collar of esses"

alt. An ornamental chain made up of interlinked or juxtaposed S's, originally worn by nobles of the House of Lancaster, and later associated by some writers with the Order of the Garter. n. An ornamental chain made up of interlinked or juxtaposed S's, originally worn by nobles of the House of Lancaster, and later associated by some writers with the Order of the Garter.