guardrail

noun

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

Synonyms of guardrail

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Examples of guardrail in a Sentence

the car ran off the road, but fortunately only hit the guardrail
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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.
Previous Tyson Group polling cited in the memo found 72% of Americans supported government guardrails on AI, while 63% were concerned that adversarial countries such as China were developing the technology faster than the United States. — Samantha-Jo Roth, The Washington Examiner, 13 Aug. 2026 Lawsuits filed and settled in 2025-26 have alleged that interactions with language models such as ChatGPT led to teen suicidal behavior and tragic losses, highlighting that commercial chatbots lack effective guardrails and crisis protocols. — Megan Kelly, The Conversation, 13 Aug. 2026 GLP-1s are now being prescribed broadly for weight loss in non-diabetic patients; and without clinical guardrails, spend does not scale linearly with clinical benefit. — Yasser Almuaala, Forbes.com, 12 Aug. 2026 When OpenAI’s model escaped and hacked a rival company, Hugging Face, leading American AI technologies refused Hugging Face’s request to analyze the attack due to their safety guardrails. — Los Angeles Times, 12 Aug. 2026 See All Example Sentences for guardrail

Word History

First Known Use

1860, in the meaning defined above

Time Traveler
The first known use of guardrail was in 1860

Rhymes for guardrail

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Browse Nearby Words

guard pin
guardrail
guard report
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Cite this Entry

“Guardrail.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/guardrail. Accessed 16 Aug. 2026.

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Kids Definition

guardrail

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