guardrail

noun

guard·​rail ˈgärd-ˌrāl 

: a railing guarding usually against danger

especially : a barrier placed along the edge of a highway at dangerous points

Synonyms of guardrail

• railing
• rail

Examples of guardrail in a Sentence

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

Recent Examples on the Web

To date, Grok and other LLMs’ only recourse is to create guardrails that flag suspicious instructions and forbid them from being executed. — Dan Goodin, ArsTechnica, 20 Aug. 2026

The other three majors have guardrails in place, from enforcing resales at face value to not permitting them at all. — Matthew Futterman, New York Times, 20 Aug. 2026

The use of noble language to describe a process that weakens constitutional guardrails only widens the disconnect between words and actions. — Yuripzy Morgan, Baltimore Sun, 20 Aug. 2026

Another big question is how easily teens can bypass new guardrails. — Gili Malinsky, CNBC, 20 Aug. 2026

Word History

First Known Use

1860, in the meaning defined above

Rhymes for guardrail

• airmail
• assail
• avail
• bewail
• blackmail
• cattail
• cocktail
• curtail
• derail
• detail
• dovetail
• email

Kids Definition

guardrail

noun

guard·​rail ˈgär-ˌdrāl 

: a protective railing placed along dangerous areas (as of a road)