SYN: By-gone, quaint, old-fashioned, obsolete.
ANT: Fashionable, modish, stylish, modern.
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KEY: Antique.
SYN: Archaic, ancient, ancestral.
ANT: Modern, recent, new-fangled.
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KEY: Antithesis.
SYN: Contrast, opposition, contradiction, antagonism.
ANT: Identity, sameness, convertibility, coincidence, coalescence.