If an action or situation is prejudicial to someone or something, it is harmful to them.
You could face up to eight years in jail for spreading rumours considered prejudicial to security.
扩散危害社会安全的谣言最高可被判入狱八年。
The judge agreed with the prosecution that such information would be too prejudicial for the jury to hear.
法官同意检方的看法,认为让陪审团知晓这些信息对断案有害无益。