casein
noun
ca·sein ˈkā-ˌsēn 
kā-ˈsēn
: a phosphoprotein of milk: such as
a
: one that is precipitated from milk by heating with an acid or by the action of lactic acid in souring and is used in making paints and adhesives
b
: one that is produced when milk is curdled by rennet, is the chief constituent of cheese, and is used in making plastics
Example Sentences
Recent Examples on the Web To start with, 100,000 wheels of the cheese will have the tiny trackers embedded in the casein label. 
Rebecca Ann Hughes, Forbes, 2 June 2022 Specifically, the chip will be inserted in the casein label, located on the rind. Michelle Cheng, Quartz, 27 May 2022 Both whey and casein protein have shown similar benefits. Sarah Schlichter, Outside Online, 11 Feb. 2021 The technology, which has been around since the 1930s, generally involves blending casein with something like acrylonitrile (the chemical used to make acrylic), making milk cotton a semi-synthetic fabric. New York Times, 22 Apr. 2021 Three weeks in, she was diagnosed with cow’s milk protein intolerance, an allergy that causes extreme gastrointestinal pain and required me to eliminate anything with lactose, whey, casein or soy from my diet. Katie Gutierrez, Time, 5 Nov. 2021 Occasionally, bottles are fined, or clarified, with animal products like egg whites, milk casein or isinglass, which comes from fish. New York Times, 15 Jan. 2021 These solids can be washed and dried to create casein protein powders. Carsen Joenk, Popular Science, 11 Jan. 2021 Common fining agents including gelatin, which is an animal product, and casein, which is a protein from milk. Tirion Morris, The Arizona Republic, 8 Dec. 2020 See More
Rebecca Ann Hughes, Forbes, 2 June 2022 Specifically, the chip will be inserted in the casein label, located on the rind. Michelle Cheng, Quartz, 27 May 2022 Both whey and casein protein have shown similar benefits. Sarah Schlichter, Outside Online, 11 Feb. 2021 The technology, which has been around since the 1930s, generally involves blending casein with something like acrylonitrile (the chemical used to make acrylic), making milk cotton a semi-synthetic fabric. New York Times, 22 Apr. 2021 Three weeks in, she was diagnosed with cow’s milk protein intolerance, an allergy that causes extreme gastrointestinal pain and required me to eliminate anything with lactose, whey, casein or soy from my diet. Katie Gutierrez, Time, 5 Nov. 2021 Occasionally, bottles are fined, or clarified, with animal products like egg whites, milk casein or isinglass, which comes from fish. New York Times, 15 Jan. 2021 These solids can be washed and dried to create casein protein powders. Carsen Joenk, Popular Science, 11 Jan. 2021 Common fining agents including gelatin, which is an animal product, and casein, which is a protein from milk. Tirion Morris, The Arizona Republic, 8 Dec. 2020 See More Word History
Etymology
probably from French caséine, from Latin caseus cheese
First Known Use
1823, in the meaning defined above
Kids Definition
casein
noun
ca·sein kā-ˈsēn
: a whitish to yellowish protein that is found in milk and cheese and is used in making paints, plastics, and adhesives
Medical Definition
casein
noun
ca·sein ˈkā-ˌsēn, ka-ˈsēn
: any of several phosphoproteins of milk: as
a
: one that occurs as a colloidal suspension in milk
called also caseinogen
b
: one that is produced when milk is curdled by rennet, is the chief constituent of cheese, and is used in making plastics
called also paracasein