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Webster 1913 Edition
Quarto
Quar′to
,Adj.
Having four leaves to the sheet; of the form or size of a quarto.
Quar′to
,Noun.
pl.
Quartos
. Originally, a book of the size of the fourth of sheet of printing paper; a size leaves; in present usage, a book of a square or nearly square form, and usually of large size.
Webster 1828 Edition
Quarto
QUART'O
,Noun.
QUART'O
,Adj.