2 definitions found

From The Collaborative International Dictionary of English v.0.44 [gcide]:

Octodecimo \Oc'to*dec"i*mo\, noun; pl. {Octodecimos}. A book composed of sheets each of which is folded into eighteen leaves; hence; indicating more or less definitely a size of book, whose sheets are so folded; -- usually written 18mo or 18[deg], and called {eighteenmo}.

From The Collaborative International Dictionary of English v.0.44 [gcide]:

Eighteenmo \Eight'een"mo\, adjective & n. See {Octodecimo}.
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