|1.||an object of sufficient age or interest to be kept in a museum|
|2.||informal a person or thing regarded as antiquated or decrepit|
An elderly or old-fashioned item or person, as in When are you going to sell that museum piece of a car? or Aunt Jane comes from another erashe's a real museum piece. This expression originated about 1900 for an article valuable enough for museum display but began to be used disparagingly from about 1915.