1A seal or stamp used to mark documents (a hanko); used in expressions like 'to stamp' (判を押す).
契約書に判を押してください。
Please stamp (put your seal on) the contract.
この書類には会社の判が必要だ。
This document requires the company's seal.
彼は重要な決定に自ら判を押した。
He personally stamped/approved the important decision.
2A judgment or decision (as in a court decision); often seen in expressions like 'a judgment is given' or 'to render a judgment.'
裁判でついに判が下された。
Finally, a judgment was handed down in the trial.
陪審の判が会社に不利に出た。
The jury's decision went against the company.
編集部が記事の掲載可否の判を下す。
The editorial department makes the decision on whether to publish the article.
3A suffix indicating the size of paper or books (e.g., A-ban, B-ban referring to size formats).
この雑誌はA判で印刷されている。
This magazine is printed in A-size format.
写真集はB判の大きさだ。
The photo book is B-size.
判型を変更して再版する予定だ。
They plan to change the format size and reprint it.