1
: a line at right angles to a goal line or end line and marking a side of a court or field of play for athletic games
2
a
: a line of goods sold in addition to one's principal line
b
: a business or activity pursued in addition to one's regular occupation
3
a
: the space immediately outside the lines along either side of an athletic field or court
b
: a sphere of little or no participation or activity
—usually plural

sideline

2 of 2

verb

sidelined; sidelining; sidelines

transitive verb

: to put out of action : put on the sidelines

Examples of sideline in a Sentence

Noun She makes and sells jewelry as a sideline.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
A couple of big names were removed from Boise State’s report ahead of Saturday’s game at Fresno State, but a few key players will also still be watching from the sideline. — Shaun Goodwin, Idaho Statesman, 8 Oct. 2026 Sunderland striker Brian Brobbey also is facing a spell on the sidelines after sustaining a hamstring injury playing for the Netherlands. — ABC News, 8 Oct. 2026
Verb
An ankle injury likely will sideline Dolphins receiver Caleb Douglas for a third consecutive game. — Barry Jackson, Miami Herald, 9 Oct. 2026 Rookie wide receiver Caleb Douglas, who is second on the team in receiving yards (113) and tied for third in receptions (seven), has also been sidelined for two games. — Chris Perkins, Sun Sentinel, 8 Oct. 2026 See All Example Sentences for sideline

Word History

First Known Use

Noun

circa 1862, in the meaning defined at sense 1

Verb

1913, in the meaning defined above

Time Traveler
The first known use of sideline was circa 1862

Browse Nearby Words

Cite this Entry

“Sideline.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sideline. Accessed 16 Oct. 2026.

Kids Definition

sideline

noun
side·​line
-ˌlīn
1
: a line marking the side of a playing field or court
2
: a business or job done in addition to one's regular occupation
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