insolvable
Word family (noun) solution solvent solubility insolvency (adjective) soluble ≠ insoluble unsolved solvent ≠ insolvent solvable ≠ insolvable (verb) solve (adverb) insolvably
From Longman Dictionary of Contemporary Englishinsolvablein‧sol‧va‧ble /ɪnˈsɒlvəbəl $ ɪnˈsɑːl-/ adjective especially American English SOLVE/DEAL WITH A PROBLEMan insolvable problem is or seems impossible to solve SYN insoluble —insolvably adverb