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midnight sun

American  
[mid-nahyt suhn] / ˈmɪdˌnaɪt ˈsʌn /

noun

  1. the sun visible at midnight in Arctic and Antarctic regions during their summer months.

midnight sun British  

noun

  1. the sun visible at midnight during local summer inside the Arctic and Antarctic circles

"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

Etymology

Origin of midnight sun

First recorded in 1855–60

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.