Isinglass

Part of speech: noun

Pronunciation: /ˈaɪzɪŋɡlɑːs/

Definitions

1. A gelatinous material derived from the dried swim bladders of fish, primarily used for clarifying beverages in the brewing and winemaking industries
2. A gelatinous substance obtained from fish bladders, primarily used as a fining agent for refining and clarifying beverages in brewing and winemaking processes
3. A clear gelatin substance extracted from the dried bladders of certain fish that helps remove impurities in drinks

Etymology: The name describes exactly what the substance is made from. Its first part comes from the German "Hausen", the name of the sturgeon, a large fish whose swim bladder yields the gelatin. The second part, "Blase", means bladder, so the original German term was essentially "sturgeon bladder". Dutch speakers adopted it as "huisenblas", and English later reshaped it into "isinglass". The change that makes the word look so strange to modern eyes happened on the English side. Once the word was in use, speakers reinterpreted its ending as "glass", perhaps because the finished material is clear and brittle when dried, and the spelling and sound drifted to match. Nothing in the word refers to glass, so the familiar second half is a false clue, an alteration rather than a meaning.