開本

book format, similar to in-4°, in-8° etc (a 16-kai format 16開|16开[shi2 liu4 kai1] is roughly A4) / abbr. to 開|开[kai1]

root / stem / origin / source / this / the current / original / inherent / originally / classifier for books, periodicals, files etc

to open / to start / to turn on / to boil / to write out (a prescription, check, invoice etc) / to operate (a vehicle) / carat (gold) / abbr. for Kelvin, 開爾文|开尔文[Kai1 er3 wen2] / abbr. for 開本|开本[kai1 ben3], book format