1. A book of quarter-sheet size.

2. Having the sheet folded into four leaves.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• quaity,
• qualty,
• quarted,
• quirty,
• quarn,
• quartr,
• quartar,
• quando,
• quaota,
• quait,
• quirte,
• quaite,
• squart,
• quarta,
• quardo,
• yearto,
• quoto,
• quata,
• quaret,
• quarte

• quirt,
• quart.

The adjective form of the word "quarto" is "quartos".

The plural of the "quarto" can be the "quartos".

The singular of the "quarto" can be the "quarto".