indoor

American  

[in-dawr, -dohr] / ˈɪnˌdɔr, -ˌdoʊr /

adjective

1. occurring, used, etc., in a house or building, rather than out of doors.

   indoor games.

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indoor British  

/ ˈɪnˌdɔː /

adjective

1. of, situated in, or appropriate to the inside of a house or other building

   an indoor tennis court

   indoor amusements

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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

She would go on to win that final 6-2 7-5 against 325th-ranked Vivian Wolff after multiple delays because of violent winds and a move to an indoor court.

From BBC • May 19, 2026

The La Calatrava property has been renovated as a three-bedroom penthouse with a rooftop terrace, a wine cellar and an indoor parking space.

From The Wall Street Journal • May 14, 2026

"I hope that they still feel welcome here," said Rob McLane, who plays indoor soccer.

From Barron's • May 13, 2026

Most western European countries ban minors from indoor tanning, as do most Canadian provinces.

From Los Angeles Times • May 6, 2026

We got running water now, and indoor plumbing, but my dad never seen no reason to tear down the old outhouse with the half-moon carved in the door.

From "The Young Man and the Sea" by Rodman Philbrick

Related Words

• private