unadulterated
adjective uk/ˌʌn.əˈdʌl.tər.eɪ.tɪd/ us/ˌʌn.əˈdʌl.ə.reɪ.t̬ɪd/
不掺杂质的，纯的
not spoiled or made weaker by the addition of other substances; pure
People injecting drugs can never be sure that they're using unadulterated substances. 注射毒品的人永远无法确定他们用的是否为纯品。
[ before noun ]完全的，彻底的
complete
a feeling of unadulterated joy 无尽的喜悦感