Synonyms for Old-hat (same or very similar meaning)
WordNet sense 1 (repeated too often; overfamiliar through overuse):
well-worn
WordNet sense 2 (not original; not being or productive of something fresh and unusual):
unoriginal
WordNet sense 3 (out of fashion):
antique, old-fashioned, outmoded, passe, passee
WordNet sense 4 (not in accord with or not following current fashion):
unfashionable, unstylish
From the ODE community, based on WordNet
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