Main entry: indissoluble, insoluble
Definition: (of a substance) incapable of being dissolved
Antonyms: soluble
Definition: (of a substance) capable of being dissolved in some solvent (usually water)
Main entry: insoluble
Definition: admitting of no solution or explanation
Usage: an insoluble doubt
Antonyms: soluble
Definition: susceptible of solution or of being solved or explained
Main entry: insoluble
Definition: without hope of solution
Usage: an insoluble problem
Antonyms: hopeful
Definition: having or manifesting hope