guard·​rail ˈgärd-ˌrāl How to pronounce guardrail (audio)
: a railing guarding usually against danger
especially : a barrier placed along the edge of a highway at dangerous points

Examples of guardrail in a Sentence

the car ran off the road, but fortunately only hit the guardrail
Recent Examples on the Web Picture those guardrails operating at different levels and with different modes of implementation. Mustafa Suleyman, WIRED, 6 Sep. 2023 Also, the guardrail is no longer necessary because speeds have been reduced on Carlsbad Boulevard, high-visibility pedestrian crossings have been installed, and additional traffic-control measures are planned. Phil Diehl, San Diego Union-Tribune, 1 Sep. 2023 Workers said Project Nimbus is the kind of lucrative contract that neglects ethical guardrails that outspoken members of Google’s workforce have demanded in recent years. Suhauna Hussain, Los Angeles Times, 30 Aug. 2023 Both groups want to put guardrails on the use of artificial intelligence. Michael Schulman, The New Yorker, 30 Aug. 2023 As a further guardrail, SynthID has three confidence levels. Harry Guinness, Popular Science, 30 Aug. 2023 That failure illustrates a more general point: guardrails are more often the result of peace, not effective methods to maintain it. Michael Beckley, Foreign Affairs, 22 Aug. 2023 Compared with other widely spoken languages, English has few guardrails against the will of the masses. S.c. Cornell, The New Yorker, 25 Aug. 2023 While some popular generative AI tools contain guardrails to prevent the most egregious privacy violations, others don’t. Alice Marwick, WIRED, 24 Aug. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'guardrail.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1860, in the meaning defined above

Time Traveler
The first known use of guardrail was in 1860

Dictionary Entries Near guardrail

Cite this Entry

“Guardrail.” Dictionary, Merriam-Webster, Accessed 25 Sep. 2023.

Kids Definition


guard·​rail ˈgär-ˌdrāl How to pronounce guardrail (audio)
: a protective railing placed along dangerous areas (as of a road)
Last Updated: - Updated example sentences
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