Adjective topnotch has 1 sense
- ace, A-one, crack, first-rate, super, tiptop, topnotch, tops - of the highest quality; "an ace reporter"; "a crack shot"; "a first-rate golfer"; "a super party"; "played top-notch tennis"; "an athlete in tiptop condition"; "she is absolutely tops"
Antonym: inferior (indirect, via superior)
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