Definition of insoluble

The word "insoluble" comes from the Latin "insolubilis," which itself derives from two Latin roots: "in-," meaning "not," and "solubilis," meaning "able to be resolved or dissolved." In the context of chemistry, "insoluble" refers to a substance that cannot be dissolved or separated into its component parts when it is mixed with a specific solvent. The first recorded use of the English word "insoluble" appeared in the late 14th century, described as meaning "difficult to explain" or "incomprehensible." It wasn't until the 15th century that the modern chemical meaning of the term came into use, as chemists began studying the interactions between substances and solvents more systematically. Today, determining whether a substance is soluble or insoluble in a particular solvent is a critical step in many scientific and industrial applications, from analyzing water quality to developing new medicines.