indoor
Americanadjective
adjective
Etymology
Origin of indoor
1705–15; aphetic variant of within-door, originally phrase within ( the ) door, i.e., inside the house
Explanation
Use the adjective indoor to describe something that happens or is used inside a building or house. Your indoor furniture is probably a little fancier than your plastic outdoor furniture. Indoor sports are the ones you play inside, like ping pong and floor hockey — beach volleyball is not an indoor sport. Your indoor voice is likewise the one you use in your house or classroom, a quieter voice than when you holler across a parking lot to your friend in his convertible. Indoor, which has been used since the 18th century, is a shortened form of the phrase within door.
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The hotel’s amenities include a spa with an 82-foot indoor pool overlooking the Thames, as well as bars and restaurants.
From The Wall Street Journal ● Sep. 2, 2026
A second possibility is to redesign indoor lighting so that it better reproduces the wavelengths present outdoors.
From Science Daily ● Aug. 26, 2026
Its revitalized city center features the Frederik Meijer Gardens & Sculpture Park, which boasts 158 acres of indoor and outdoor botanic gardens, nature trails and a massive sculpture collection.
From MarketWatch ● Aug. 25, 2026
Zach told the outlet that he made plans to get lunch and play indoor golf with his brother and the actor after church on Sunday morning.
From Los Angeles Times ● Aug. 22, 2026
Nevertheless, they had sent him an e-mail telling him, after he landed in Las Vegas, to meet them not at the conference but at this indoor shooting range, a few miles from the strip.
From "The Big Short" by Michael Lewis
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.
