de rigueur is a
French expression that literally means "of rigor" or "of strictness". In
English language usage, it means, "necessary according to etiquette, protocol or fashion."Something that is de rigueur is required by convention or fashion, but not by any hard rule. For example, among the upper classes during the
Victorian era, dressing for dinner was de rigueur. In modern times, it is considered de rigueur among many wealthy
New York City residents to own a weekend house in
the Hamptons.
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