• synonyms


  1. a line at the side of something.
  2. a business or activity pursued in addition to one's primary business; a second occupation.
  3. an additional or auxiliary line of goods: a grocery store with a sideline of household furnishings.
  4. Sports.
    1. either of the two lines defining the side boundaries of a field or court.
    2. sidelines,the area immediately beyond either sideline, where the substitute players sit.
  5. sidelines, the position or point of view taken by a person who observes an activity or situation but does not directly participate in it.
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verb (used with object), side·lined, side·lin·ing.
  1. to render incapable of participation, especially in anything involving vigorous, physical action, as a sport: An injury to his throwing arm sidelined the quarterback for two weeks.
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Origin of sideline

An Americanism dating back to 1685–95; side1 + line1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for sidelines

recreation, diversion, subsidiary, hobby, distraction, moonlighting

Examples from the Web for sidelines

Contemporary Examples of sidelines

Historical Examples of sidelines

  • From the sidelines it seemed as though they were wrestling with an invisible octopus.

  • The sidelines of the gang came through force of circumstances.

    Jack O' Judgment

    Edgar Wallace

  • Bill and Lee, on the sidelines by the hangars, did not find all this very exciting.

    Battling the Clouds

    Captain Frank Cobb

  • No one in all the world would have given so much to watch it from the sidelines.

    Red Dynamite

    Roy J. Snell

  • Johnny whispered as he crouched on the sidelines waiting for action.

    Red Dynamite

    Roy J. Snell

British Dictionary definitions for sidelines


pl n
  1. sport the area immediately outside the playing area, where substitute players sit
  2. the peripheral areas of any region, organization, etc
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  1. sport a line that marks the side boundary of a playing area
  2. a subsidiary interest or source of income
  3. an auxiliary business activity or line of merchandise
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verb (tr)
  1. to prevent (a player) from taking part in a game
  2. to prevent (a person) from pursuing a particular activity, operation, career, etc
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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

Word Origin and History for sidelines



also side-line, "line on the side of a fish," 1768; "lines marking the limits of playing area" (on a football field, etc.), 1862, from side (adj.) + line (q.v.). Meaning "course of business aside from one's regular occupation" is from 1890. Railway sense is from 1890. The figurative sense of "position removed from active participation" is attested from 1934 (from the railway sense or from sports, because players who are not in the game stand along the sidelines). The verb meaning "put out of play" is from 1945. Related: Sidelined; sidelining.

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Online Etymology Dictionary, © 2010 Douglas Harper

Idioms and Phrases with sidelines


see on the sidelines.

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The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.