plural -s
: the size (approximately 4 by 6.5 inches) of a piece of paper cut 18 from a sheet
also : paper or a page of this size
abbreviation 18mo
symbol 18°

Word History


eighteen + -mo (as in duodecimo)

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Dictionary Entries Near eighteenmo

Cite this Entry

“Eighteenmo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/eighteenmo. Accessed 20 Jul. 2024.

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