insoluble Synonyms

not soluble indissoluble inexplicable undissolvable unanalyzable nonsolvable unsolvable unexplainable undecidable unfathomable undeterminable unanswerable unaccountable thorny strange solubility practically insoluble undoable hardly soluble non-dissolvable non-soluble unable to dissolve incapable of being dissolved not dissolvable without a solution undividable unable to be solved incapable of dissolving unsoluble unsolved unresolvable unexcogitable puzzling perplexing obscure incomprehensible impossible impenetrable hard gordian extricable extirpable enigmatic difficult complicated complex bewildering baffling indecomposable indissolvable