The definition of insoluble is something that cannot be solved or dissolved.(adjective)
An example of something insoluble is a cryptic phrase in an old mystery book that people have been trying to uncode for centuries.
See insoluble in Webster's New World College Dictionary
Origin: ME insolible < L insolubilis
See insoluble in American Heritage Dictionary 4
Origin: Middle English insolible
Origin: , from Latin īnsolūbilis
Origin: : in-, not; see in-1
Origin: + solvere, to loosen; see soluble.
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