twelvemo

noun

twelve·mo ˈtwelv-(ˌ)mō

plural twelvemos

: the size of a piece of paper cut 12 from a sheet

also : a book, a page, or paper of this size

Word History

First Known Use

1816, in the meaning defined above

Time Traveler

The first known use of twelvemo was in 1816

See more words from the same year

Cite this Entry

Style

“Twelvemo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/twelvemo. Accessed 30 Oct. 2025.

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