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double-nickel

American  
[duhb-uhl-nik-uhl] / ˈdʌb əlˈnɪk əl /

noun

Slang.

  1. the national speed limit of 55 miles per hour as established in 1974 on U.S. highways.

Etymology

Origin of double-nickel

First recorded in 1975–80

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

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