名詞 quarto:

1. the size of a book whose pages are made by folding a sheet of paper twice to form four leaves
   同義詞：4to

quar.to

n.（名詞）
【復數(shù)】 quar.tos 縮寫 q.,Q.,qto.
The page size obtained by folding a whole sheet into four leaves.
四開：將一張紙折疊成四頁而獲得的紙張尺寸
A book composed of pages of this size.
四開本：由這樣大小的紙張組成的書籍

來源：
Short for Middle English (in) quarto [(in) the fourth part (of a sheet)]
中古英語 (in) quarto的簡寫 [（位于一張紙的）第四部分]
from Medieval Latin (in) qu3rtô
源自 中世紀拉丁語 (in) qu3rtô
from Latin [ablative of] qu3rtus [fourth] * see k wetwer-
源自 拉丁語 [] qu3rtus的奪格 [第四] *參見 k wetwer-