From Longman Dictionary of Contemporary Englishetiquetteet‧i‧quette /ˈetɪket $ -kət/ noun [uncountable]RULE/REGULATIONthe formal rules for politebehaviour in society or in a particular groupstrict rules of professional etiquetteExamples from the Corpusetiquette• Etiquette is especially important on occasions such as weddings and funerals.• Ever a stickler for protocol, he and his wife took umbrage at the democraticetiquette of President Thomas Jefferson's administration.• It was considered a breach of etiquette to refuse an invitation.• The royal family could be relied upon as paragons of etiquette.• The instructor, who is always addressed as the sensei, instilsprinciples of etiquette into every student.• They will in this respectresemble our own rules of etiquette.• Professionaletiquettedictates that judges should not express their opinions about a case in public.• When it comes to racingetiquette and forthrightlanguage, Mario has few equals.• She spoke effusively, implying more enthusiasm than etiquette required.• After dinner the etiquette was very stiff, and we stood for two hours.From Longman Business Dictionaryetiquetteet‧i‧quette /ˈetɪket-kət/ noun [uncountable]the formal rules for behaviourthe professional rules of etiquette imposed by the Law SocietyBusiness etiquette (=rules for behaviour by businesspeople) is still very important in corporate Japan. → see alsonetiquetteOriginetiquette(1700-1800)Frenchétiquette"ticket" ( → TICKET1); perhaps because rules of behavior were written on a small card, like a ticket