Science, Tech, Math › Science Gel Definition in Chemistry Share Flipboard Email Print Image Source / Getty Images Science Chemistry Chemical Laws Basics Molecules Periodic Table Projects & Experiments Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate By Anne Marie Helmenstine, Ph.D. Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. our editorial process Facebook Facebook Twitter Twitter Anne Marie Helmenstine, Ph.D. Updated January 16, 2020 A gel is a sol in which the solid particles are meshed such that a rigid or semi-rigid mixture results. Cross-linking within the gel's polymer or colloidal network causes a gel to behave as a solid in its steady-state and makes it feel tacky. However, most of the mass of a gel is liquid, so gels can flow from application of relatively low stress. 19th-century Scottish chemist Thomas Graham coined the word "gel" by shortening the word "gelatine." Gel Examples Fruit jelly is an example of a gel. Cooked and cooled gelatin is another example of a gel. The protein molecules of gelatin cross-link to form a solid mesh which contains pockets of liquid. Sources Ferry, John D. Viscoelastic Properties of Polymers. New York: Wiley. (1980). ISBN 0471048941.Khademhosseini, A. und U. Demirci. Gels Handbook: Fundamentals, Properties and Applications. World Scientific Pub Co Inc. (2016). ISBN 9789814656108.