HO scale

noun

(ˈ)ā-ˈchō- How to pronounce HO scale (audio)
: a scale of 3.5 millimeters to one foot used especially for model toys (such as automobiles or trains)

Word History

Etymology

half + O (gauge)

First Known Use

1939, in the meaning defined above

Time Traveler
The first known use of HO scale was in 1939

Rhymes for HO scale

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Browse Nearby Words

hosanna
HO scale
hose
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Cite this Entry

“HO scale.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/HO%20scale. Accessed 5 Jul. 2026.

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