Antonyms of adj top-notch

1 sense of top-notch

Sense 1
ace, A-one, crack, first-rate, super, tiptop, topnotch, top-notch, tops (predicate) -- (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")

INDIRECT (VIA superior) -> inferior -- (of low or inferior quality)
                                                                         

Similarity of adj top-notch

1 sense of top-notch

Sense 1
ace, A-one, crack, first-rate, super, tiptop, topnotch, top-notch, tops (predicate) -- (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")
       => superior (vs. inferior) -- (of high or superior quality or performance; "superior wisdom derived from experience"; "superior math students")