meniscus

American  

[mi-nis-kuhs] / mɪˈnɪs kəs /

noun

plural

menisci, meniscuses

1. a crescent or a crescent-shaped body.

2. the convex or concave upper surface of a column of liquid, the curvature of which is caused by surface tension.

3. Optics. a lens with a crescent-shaped section; a concavo-convex or convexo-concave lens.

4. Anatomy. a disk of cartilage between the articulating ends of the bones in a joint.

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meniscus British  

/ mɪˈnɪskəs /

noun

1. the curved upper surface of a liquid standing in a tube, produced by the surface tension

2. a crescent or half-moon-shaped body or design

3. a crescent-shaped fibrous cartilage between the bones at certain joints, esp at the knee

4. a crescent-shaped lens; a concavo-convex or convexo-concave lens

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meniscus Scientific  

/ mə-nĭs′kəs /

plural

menisci

1. A lens that is concave on one side and convex on the other.

2. The curved upper surface of a column of liquid in a container. The surface is concave if the molecules of the liquid are attracted to the container walls and convex if they are not.

3. See also surface tension

4. A piece of cartilage shaped like a crescent and located at the junction of two bones in a joint. The meniscus acts to absorb shock.

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Other Word Forms

• meniscoid adjective

Etymology

Origin of meniscus

1685–95; < New Latin < Greek mēnískos crescent, diminutive of mḗnē moon

Explanation

The next time you pour some fluid into a tube, look at it from the side. You will see the liquid has a slight curve, either up or down. This curved surface, created by air pressure, is called a meniscus. The Greeks had a word for the lunar crescent, mēniskos, which itself came from the word for the moon, mḗnē. In the late 17th Century, the word meniscus was given to similarly-curved lenses. Then in 1812, the curved surfaces of liquid were referred to by this word as well. Later, the name was also applied to a crescent-shaped cartilage at the knee, between the tibia and the femur. These small, semi-lunar bits are important for reducing friction during leg movement.

Example Sentences

Then, within days of finally being cleared to practice during the summer at USC, Arenas learned his meniscus was torn.

From Los Angeles Times • Mar. 11, 2026

"But let's see how they respond, with no cartilage and no meniscus..."

From BBC • Feb. 15, 2026

She says along with the ACL tear she also has bruising and meniscus damage.

From BBC • Feb. 3, 2026

She added that she had also suffered bone bruising and meniscus damage from her fall in a race which was abandoned early due to awful conditions which caused two other crashes.

From Barron's • Feb. 3, 2026

In addition to the double lens fittings these cameras are also offered with single meniscus achromatic lenses for those who prefer compact folding cameras requiring but little adjustment of focus for objects at different distances.

From Premo Cameras 1914 by Canadian Kodak Company

Related Words

• arc
• arch
• contour
• loop
• trajectory