undesirable /ˌʌndiˈzaiərəbl/ adj. 不合需要的；令人不快的；讨厌的：undesirable behavior 令人讨厌的行为；the drug's undesirable side effects药的不良副作用；a situation which is highly undesirable非常麻烦的情况 It is clearly undesirable for the issue to be ignored.这个问题显然不容忽视。It was felt that the ageing of society was socially and economically undesirable.老龄化对于社会和经济的不良影响呈现出来了。