noun eigh·teen·mo

Definition of eighteenmo



  1. :  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°

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Origin and Etymology of eighteenmo

eighteen + -mo (as in duodecimo)

Seen and Heard

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to criticize severely

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