thickness

American  

[thik-nis] / ˈθɪk nɪs /

noun

1. the state or quality of being thick.

2. the measure of the smallest dimension of a solid figure.

   a board of two-inch thickness.

3. the thick part or body of something.

   the thickness of the leg.

4. a layer, stratum, or ply.

   three thicknesses of cloth.

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verb (used with object)

1. to bring (a piece, as a board) to a uniform thickness.

thickness British  

/ ˈθɪknɪs /

noun

1. the state or quality of being thick

2. the dimension through an object, as opposed to length or width

3. a layer of something

4. a thick part

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Etymology

Origin of thickness

before 900; Middle English thiknesse, Old English thicnes. See thick, -ness

Explanation

The word thickness refers to the distance between the sides of an object, or how dense and solid something feels — like the weight of a cozy blanket or the richness of a creamy soup. Thickness can refer to the physical width of an item, like the thickness of a book or a slice of bread. It can also describe the concentration of a substance, such as the thickness of paint on a wall. Thickness can even describe something’s heaviness or sturdiness, like the solid weight of a durable winter coat.

Example Sentences

Weatherhead says the thickness of the skin affects how well red light can penetrate.

From BBC • May 2, 2026

They maintained that frequently used regions of the brain received increased blood flow and that the skull’s shape and thickness were affected as a result.

From The Wall Street Journal • Apr. 29, 2026

The base was rich, but it lacked the kind of body that makes a chowder feel finished: the subtle thickness, the quiet cohesion.

From Salon • Apr. 16, 2026

In the Arctic, however, sea ice has thinned dramatically, with average thickness falling from 3.59 metres in 1975 to 1.25 meters in 2012, according to a 2015 study.

From Barron's • Mar. 11, 2026

Olanna had stared at him, at the arch of his eyebrows behind the glasses, the thickness of his body, already thinking of the least hurtful way to untangle herself from Mohammed.

From "Half of a Yellow Sun" by Chimamanda Ngozi Adichie

Related Words

• consistency
• density
• diameter
• dimension
• girth
• layer
• sheet
• width