In a manner that fails to satisfy; in an unsatisfactory or disappointing way.
From 'dissatisfactory' (adjective) plus the adverbial suffix '-ly.' The base adjective combines 'dis-' with 'satisfactory,' negating the positive quality of being satisfying.
This is a wonderfully long word that takes eight syllables to say 'not satisfactorily'—English speakers sometimes create these lengthy negations instead of using simpler opposites, possibly because the negation feels more formal or official!
Complete word intelligence in one call. Free tier — 50 lookups/day.