The act of altering, falsifying, or tampering with documents, data, or records; often used for illegal or fraudulent modifications.
会社の帳簿が改ざんされていることが発覚した。
It was discovered that the company's books had been falsified.
研究データの改ざんは学問上の重大な違反だ。
Falsifying research data is a serious academic offense.
選挙結果の改ざんを疑う声が上がった。
Voices arose suspecting tampering with the election results.