: a scale of 3.5 millimeters to one foot used especially for model toys (such as automobiles or trains)

Word History


half + O (gauge)

First Known Use

1939, in the meaning defined above

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

Dictionary Entries Near HO scale

Cite this Entry

“HO scale.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/HO%20scale. Accessed 22 Mar. 2023.

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