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.

---

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

---

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

The experiment begins with an intense burst of light striking a very thin copper wire, about one-seventh the thickness of a human hair.

From Science Daily • May 1, 2026

Chicken cutlet starts with either a boneless chicken thigh or a boneless chicken breast that’s covered with cling wrap and pounded to even thickness.

From Salon • Feb. 26, 2026

The revision comes months after Airbus found what it described as a “supplier-quality issue” relating to the thickness of metal panels used to make its A320 line of jets.

From The Wall Street Journal • Feb. 19, 2026

The shacks were built of one thickness of pine planking covered with tarpaper.

From "Farewell to Manzanar" by Jeanne Houston

Related Words

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