Etymology From Middle English thikkenesse, thiknesse, from Old English þicnes (“thickness, viscosity, density, hardness; obscurity, cloud, darkness; thicket; depth, a thick body, anything thick or heavy”), from Proto-West Germanic *þikkwīnassī (“thickness”), equivalent to thick + -ness. Cognate with West Frisian tsjokkens (“thickness”), Old High German dickinessī, dikkinissi, diknissi (“thickness, density”). Eclipsed non-native Middle English crassitude (“thickness”) from Latin crassitūdō (“thickness”).
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The property of being thick (in dimension).
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A measure of how thick (in dimension) something is.
The thickness of the Earth's crust varies from two to 70 kilometres.
Guitar picks come in different thicknesses.
2 more examples
The newest form of gold created in a lab is the thickness of two atoms, according to a new study. It’s only 0.47 nanometers thick, which is one million times thinner than a human finger nail.2019 August 6, Ashley Strickland, “Scientists just created the world’s thinnest gold and it’s two atoms thick”, in CNN:
Whether made by a small business or a household name like Scotch, washi tape comes in countless colors, patterns and thicknesses and can be used for just as many adhesive-related projects, from decorating envelopes and empty jars to creating section dividers and adhering photos/ephemera in journals.2025 January 6, Daniel Toy, “I’ve been journaling for more than 20 years. Here are my 25 favorite journaling supplies”, in CNN:
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A layer.
We upholstered the seat with three thicknesses of cloth to make it more comfortable to sit on.
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The quality of being thick (in consistency).
Whip the cream until it reaches a good thickness.
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Informal The property of being thick (slow to understand).
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Graph theory, Mathematics, Sciences The minimum number of planar subgraphs which a given graph can decompose into.
Etymology From Middle English thikkenesse, thiknesse, from Old English þicnes (“thickness, viscosity, density, hardness; obscurity, cloud, darkness; thicket; depth, a thick body, anything thick or heavy”), from Proto-West Germanic *þikkwīnassī (“thickness”), equivalent to thick + -ness. Cognate with West Frisian tsjokkens (“thickness”), Old High German dickinessī, dikkinissi, diknissi (“thickness, density”). Eclipsed non-native Middle English crassitude (“thickness”) from Latin crassitūdō (“thickness”).
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To trim (wood) to a consistent thickness using a thickness planer.
Even if the parts are thicknessed by machine, check for and plane out any cup with a bench plane.2003, Garrett Hack, The Handplane Book, page 143: