Used for the alcohol proof scale, especially in imported liquor contexts.
このウイスキーは80プルーフです。
This whiskey is 80 proof.
Appears in compound loanwords such as ウォータープルーフ (waterproof). Rarely used as a standalone noun.
この時計はウォータープルーフです。
This watch is waterproof.
A trial print for checking before final printing. The Japanese term 校正刷り is more common.
See also: 校正刷り
デザイナーは印刷前にプルーフを確認した。
The designer checked the proof before printing.
General sense of evidence or verification, often in technical or formal contexts. 証拠 is the common Japanese equivalent.
その理論には確かなプルーフが必要だ。
That theory needs solid proof.
proof coin
underproof
windproof · windproof jacket
overproof
Borrowed from English 'proof', used in several specialized senses.