Old-hat and Past

Old-hat adjective - Repeated too often; overfamiliar through overuse.

Past and old-hat are semantically related. in old-fashioned topic. In some cases you can use "Past" instead an adjective phrase "Old-hat", when it comes to topics like antiquated.

Past adjective - Having been such at some previous time.

Old-hat and past are semantically related. Sometimes you can use "Old-hat" instead an adjective "Past".