isinglass

American  

[ahy-zuhn-glas, -glahs, ahy-zing-] / ˈaɪ zənˌglæs, -ˌglɑs, ˈaɪ zɪŋ- /

noun

1. a pure, transparent or translucent form of gelatin, obtained from the air bladders of certain fish, especially the sturgeon: used in glue and jellies and as a clarifying agent.

2. mica, especially in thin, translucent sheets.

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isinglass British  

/ ˈaɪzɪŋˌɡlɑːs /

noun

1. a gelatine made from the air bladders of freshwater fish, used as a clarifying agent and adhesive

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isinglass Scientific  

/ ī′zən-glăs′,ī′zĭng- /

1. A transparent, almost pure gelatin prepared from the inner membrane of the swim bladder of the sturgeon and certain other fishes. It is used as an adhesive and a clarifying agent.

2. Mica, especially in the form of the mineral muscovite.

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Etymology

Origin of isinglass

1535–45; < Middle Dutch huysenblase (with glass for blase by folk etymology), literally, sturgeon bladder; cognate with German Hausenblase

Example Sentences

Bentonite clay, gelatin, egg albumin from egg whites, purified milk proteins called casein and isinglass made from the bladders of sturgeons, are all used to filter the wine through a process called “fining.”

From National Geographic • Jul. 20, 2023

Each flake of ancient paint was treated with a tiny drop of isinglass, a natural collagen obtained from the swim bladder of a sturgeon, which was applied, heated and pressed down to match the surface.

From New York Times • Dec. 19, 2016

"I think with the craft beer revolution more breweries aren't using isinglass," said Mr Bosworth.

From BBC • Sep. 14, 2016

It is unlikely the swim bladder of fish would be on the list, but isinglass - a gelatine made using the organ - is in fact very likely to be in your average pint.

From BBC • Sep. 14, 2016

He kept the isinglass curtains snapped to the windows to cut off the draughts, and tight around his neck he wore his gray wool shawl.

From "The Heart is a Lonely Hunter" by Carson McCullers