arcus

[ahr-kuhs]

noun

Meteorology.

plural

arcus 

1. a dense, horizontal, roll-shaped cloud sometimes occurring at the lower front portion of a cumulonimbus.

Word History and Origins

Origin of arcus¹

< Latin: bow, arch

Example Sentences

Video shows a shelf cloud - a type of arcus cloud - form before a thunderstorm hit Portland.

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To Cassiopeia, she added, “Next time, try pluvius arcus, dear; the meaning is clearer.”

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This must be distinguished from the true fatty arcus senilis.

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Moreover, there is the arcus senilis, the fine translucent to opaque circle surrounding the outer portion of the iris.

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Because xanthelasmata are composed of foam cells similar to those present in atherosclerotic plaque, they may be a better marker than arcus corneae of the intra-arterial atherosclerotic process.”

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