a. [ L. insolubilis indissoluble, that can not be loosed: cf. F. insoluble. See In- not, and Soluble, and cf. Insolvable. ] [ 1913 Webster ]
1. Not soluble; in capable or difficult of being dissolved, as by a liquid; as, chalk is insoluble in water. [ 1913 Webster ]
2. Not to be solved or explained; insolvable; as, an insoluble doubt, question, or difficulty. [ 1913 Webster ]
3. Strong. “An insoluble wall.” [ Obs. ] Holland [ 1913 Webster ]
n. The quality or state of being insoluble; insolubility. Boyle. [ 1913 Webster ]