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sundog

American  
[suhn-dawg, -dog] / ˈsʌnˌdɔg, -ˌdɒg /
Or sun dog

noun

  1. parhelion.

  2. a small or incomplete rainbow.

sundog British  
/ ˈsʌnˌdɒɡ /

noun

  1. another word for parhelion

  2. a small rainbow or halo near the horizon

"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 sundog

First recorded in 1625–35; origin uncertain

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.