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OO gauge

American

[oh-oh] / ˈoʊˈoʊ /

noun

a model railroad gauge of 3/4 inch (19 millimeters).

Etymology

Origin of OO gauge

First recorded in 1920–25

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.