Old hat
The phrase "old hat" typically means something that is outdated, obsolete, or no longer new or interesting. It refers to a concept, idea, or fashion trend that has become overly familiar or widely known. It implies that the subject in question is no longer fresh or exciting and may be worn out or passe.
An idiom is a phrase or expression that usually presents a figurative, non-literal meaning attached to the phrase. Does that sound fun? It can be!
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