plural silicones
: any of various synthetic polymers that are manufactured in various forms (such as elastomer, resin, oil, and gel), that are used in a variety of applications (such as electronic components, medical devices, bakeware, automotive engine parts, and construction sealants), that are characterized especially by chemical inertness, water repellency, and resistance to ultraviolet light and extreme heat, and that have flexible silicon and oxygen bonds in the backbone (see backbone sense 2c)
Instead of greasing, you can line the cookie sheets with parchment paper or a baking mat made from siliconeSuzanne Boyle
For concerns about traveling with anything wet … look for heavy-duty reusable bags made from silicone, which is not compostable but can be reused more frequently than a plastic bag.Mindy Sink
Every other year or so, it's important to seal these cracks with rubber siliconeKen Moon
often used before another noun
You can keep your garage door operating smoothly by lubricating the tracks with a small amount of silicone spray.Angie Hicks
… surgery filled the tear in the eye with silicone oil to keep the shape and give the retina a chance to reattach at the back of the eye.Mike Wilson
see also silicone rubber

Examples of silicone in a Sentence

a prosthesis made of silicone
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The silicone or rubber rings that make containers airtight are also where mold and bacteria hide. Sarah Anzlovar, Verywell Health, 18 Sep. 2026 Rubber or silicone gloves for protection while cleaning or doing the dishes. Maggie Ryan, Flow Space, 18 Sep. 2026 Engineered at the molecular level, this new non-porous material remains rock-hard and even stops heat transfer five times more effectively than soft silicone. Mrigakshi Dixit, Interesting Engineering, 18 Sep. 2026 Cutting boards, wooden spoons, silicone utensils, dishes, countertops, and even your hands can all fall victim to turmeric’s yellow-orange pigment. Jessica Safavimehr, Southern Living, 17 Sep. 2026 See All Example Sentences for silicone

Word History

Etymology

silicon + -one

First Known Use

1944, in the meaning defined above

Time Traveler
The first known use of silicone was in 1944

Cite this Entry

“Silicone.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/silicone. Accessed 24 Sep. 2026.

Kids Definition

silicone

noun
: any of various silicon compounds that contain carbon and hydrogen, are obtained as oily or greasy substances or plastics, and are used especially for water-resistant and heat-resistant lubricants and varnishes

Medical Definition

silicone

noun
: any of various polymeric organic silicon compounds which are obtained as oils, greases, or plastics and some of which have been used as surgical implants

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