ㄨㄟˊㄌㄧㄤˋwéiliàngㄩㄢˊㄙㄨˋyuánsù

wēiliàng yuánsùㄨㄟ ㄌㄧㄤˋ ㄩㄢˊ ㄙㄨˋ
  1. 生物正常生活必需需求化學元素

trace element (chemistry)​
Micro-élément
Spurenelement (S, Chem)​