1. Etiquette, decorum, propriety

imply observance of the formal requirements governing behavior in polite society. Etiquette refers to conventional forms and usages: the rules of etiquette. Decorum suggests dignity and a sense of what is becoming or appropriate for a person of good breeding: a fine sense of decorum. Propriety (usually plural) implies established conventions of morals and goodtaste: She never fails to observe the proprieties

The French word étiquette, literally signifying a tag or label