sidelight

American  

[sahyd-lahyt] / ˈsaɪdˌlaɪt /

noun

1. an item of incidental information.

2. either of two lights carried by a vessel under way at night, a red one on the port side and a green on the starboard.

3. light coming from the side.

4. a window or other aperture for light in the side of a building, ship, etc.

5. a window at the side of a door or another window.

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sidelight British  

/ ˈsaɪdˌlaɪt /

noun

1. light coming from the side

2. a side window

3. either of the two navigational running lights used by vessels at night, a red light on the port and a green on the starboard

4. either of two small lights on the front of a motor vehicle, used to indicate the presence of the vehicle at night rather than to assist the driver

5. additional or incidental information

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Etymology

Origin of sidelight

First recorded in 1600–10; side ¹ + light ¹

Example Sentences

Matthiessen considered his nonfiction career a sidelight to his real literary endeavors.

From The Wall Street Journal • Nov. 21, 2025

After four decades, Chapman's "sidelight" has become an American nightmare.

From Salon • Dec. 15, 2022

An interesting sidelight not noted by Enrich is that Insys was the inspiration for “Quichotte,” a 2019 novel by Salman Rushdie.

From New York Times • Feb. 9, 2022

The courtyards will receive some visible daylight — sidelight — and will showcase three-dimensional installations as well as works that don’t require highly controlled lighting conditions.

From Los Angeles Times • Sep. 17, 2020

I rang the doorbell and heard Myrna Mountweazel’s paws scurrying on the hardwood floors, and then she was barking like crazy, staring at us through the sidelight glass.

From "Paper Towns" by John Green