old hat[adjective]Synonyms: old-fashioned, antiquated, antique, archaic, dated, démodé, oldfangled, old-time, out-of-date, vintage, trite, cliché, clichéd, hackneyed, shopworn, stale, threadbare, timeworn, tired, well-worn
[TahlilGaran] English Synonym Dictionary ▲
ˌold ˈhat adjective [not before noun] if something is old hat, a lot of people have said or done the same thing before and it is therefore not new or interesting:
Most of this is probably old hat to you, isn’t it? [TahlilGaran] Dictionary of Contemporary English ▲