18mo

Fetched 2026-10-26 (cache).

Datamuse reports no synonyms or antonyms for this word.

Noun

1. {{lb|en|paper}} {{abbreviation of|en|octodecimo|addl=a [[page]] [[size]]}}.
2. {{lb|en|printing}} A book size octodecimo-sized pages.

Source: Wiktionary · CC BY-SA 4.0 (Wiktionary dump) · cached copy, not a rewrite.