guard·​rail | \ˈgärd-ˌrāl \

Definition of guardrail 

: a railing guarding usually against danger especially : a barrier placed along the edge of a highway at dangerous points

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Synonyms for guardrail


balustrade, banister (also bannister), rail, railing

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Examples of guardrail in a Sentence

the car ran off the road, but fortunately only hit the guardrail

Recent Examples on the Web

To avert a terrible accident, the international biomedical community should establish firmer cultural guardrails on the research into pathogens. R. Daniel Bressler, Vox, "“Designer bugs”: how the next pandemic might come from a lab," 6 Dec. 2018 Nowhere have the challenges been steeper than Big Thompson Canyon, where floodwaters scoured away not only pavements and guardrails but roadbeds and subsurface geology, effectively leaving sections of highway unsound and unsafe. Daniel Cusick, Scientific American, "Colorado Charts a New Path Away from Floodwaters," 25 May 2018 Some companies, including Google and Microsoft, have set up internal ethics processes or guidelines to put guardrails around their use of the technology. Tom Simonite, WIRED, "A Plea for AI That Serves Humanity Instead of Replacing It," 22 June 2018 The rule includes guardrails to prevent employers from dumping sick employees onto the exchanges, and to prevent a person from getting both employer contributions and public subsidies. The Editorial Board, WSJ, "Trump’s Health-Care Progress," 4 Nov. 2018 This guardrail was intended to prevent states from enacting plans that would leave consumers with inadequate insurance coverage, as often happened before the health-care law was enacted. Noam N. Levey, The Seattle Times, "Trump administration takes another step to allow plans that don’t cover pre-existing health conditions," 22 Oct. 2018 Limitations and guardrails aren’t problems—they’re an invitation to think a little differently. Liz Stinson, Curbed, "These tiny apartments show how to live cozy in 270 square feet," 26 July 2018 Other work on the Atlantic Avenue interchange will include: — Widening the northbound entrance ramp from Atlantic Avenue. — Adding guardrails, signs, lights, pavement markings and electronic display signs for safety. Marci Shatzman,, "Turbo lane expected to ease tie-ups at I-95 and Atlantic Avenue," 13 July 2018 The Detroit area boasts two major testing sites for autonomous vehicles, sprawling compounds of interstates, guardrails, and mock pedestrians and bicyclists that companies and researchers use to test their technology. New York Times, "Trump’s Trade War With China Pierces the Heart of Michigan," 12 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'guardrail.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of guardrail

1860, in the meaning defined above

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Statistics for guardrail

Last Updated

12 Dec 2018

Look-up Popularity

Time Traveler for guardrail

The first known use of guardrail was in 1860

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More Definitions for guardrail



English Language Learners Definition of guardrail

: a strong metal bar along the side of a road that prevents vehicles from driving off the road

: a strong bar or fence that prevents people from falling off a deck, bridge, etc.

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More from Merriam-Webster on guardrail

Rhyming Dictionary: Words that rhyme with guardrail

Thesaurus: All synonyms and antonyms for guardrail

Spanish Central: Translation of guardrail

Comments on guardrail

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having a pattern of small flowers

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