meniscus

English

WOTD – 20 July 2008

A: The bottom of a concave meniscus.
B: The top of a convex meniscus.

Notional section through Meniscus lens, showing it to be concavo-convex, with a positive focus because it is thicker in the middle than the edge

Etymology

From Ancient Greek μηνίσκος (mēnískos, “crescent”), from μήνη (mḗnē, “moon”)

Pronunciation

• (UK, US) IPA^(key): /mɛˈnɪs.kəs/, /məˈnɪs.kəs/

• Audio (US)

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• Audio (AU)

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Noun

meniscus (plural meniscuses or menisci)

1. A crescent moon, or an object shaped like it. [from 17th c.]
   • 1972, Vladimir Nabokov, Transparent Things, McGraw-Hill 1972, p. 19:

     He opened wide both casements; they gave on a parking place four floors below; the thin meniscus overhead was too wan to illumine the roofs of the houses descending toward the invisible lake [...].

2. (optics) A lens which is convex on one side and concave on the other, being crescent-shaped in cross-section. [from 17th c.]
3. The curved surface of liquids in tubes, whether concave or convex, caused by the surface tension of the liquid. [from 19th c.]
4. (anatomy) Either of two parts of the human knee that provide structural integrity to the knee when it undergoes tension and torsion. [from 19th c.]

Translations

the curved surface of liquids

• Catalan: menisc (ca) m
• Chinese:

  Mandarin: 弯月面 (zh) (hans), 彎月面 (zh) (hant)

• French: ménisque (fr) m
• German: Meniskus (de) m

• Latvian: menisks m
• Maori: mata kōpapa
• Polish: menisk m
• Russian: мени́ск (ru) m (menísk)
• Spanish: menisco (es) m

a crescent

• French: ménisque (fr) m

• Russian: мени́ск (ru) m (menísk)

either of two parts of the human knee

• Catalan: menisc (ca) m
• Chinese:

  Mandarin: 半月板 (zh)

• Czech: meniskus m
• French: ménisque (fr) m

• Latvian: menisks m
• Polish: łękotka (pl) f
• Russian: мени́ск (ru) m (menísk)
• Spanish: menisco (es) m
• Swedish: menisk (sv) c

See also

• lunette