sunspot

[ suhn-spot ]

noun
  1. one of the relatively dark patches that appear periodically on the surface of the sun and affect terrestrial magnetism and certain other terrestrial phenomena.

Origin of sunspot

1
First recorded in 1805–15; sun + spot

Other words from sunspot

  • sunspotted, adjective
  • sun·spot·ted·ness, noun

Words Nearby sunspot

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use sunspot in a sentence

British Dictionary definitions for sunspot

sunspot

/ (ˈsʌnˌspɒt) /


noun
  1. any of the dark cool patches, with a diameter of up to several thousand kilometres, that appear on the surface of the sun and last about a week. They occur in approximately 11-year cycles and possess a strong magnetic field

  2. informal a sunny holiday resort

  1. Australian a small cancerous spot produced by overexposure to the sun

Derived forms of sunspot

  • sunspotted, adjective

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for sunspot

sunspot

[ sŭnspŏt′ ]


  1. Any of the dark, irregular spots that usually appear in groups on the surface of the Sun (its photosphere), lasting from a few days to several weeks or more. Sunspots appear dark because they are cooler, by up to 1,500°K, than the surrounding photosphere. They are associated with strong magnetic fields and solar magnetic storms moving in a vortex pattern, similar to a tornado on Earth. The number of sunspots waxes and wanes over an 11-year period; at maximum activity there are often increased numbers of solar flares.

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