1. The state or quality of being impure; presence of unwanted or unclean substances
The water contained impurities that made it undrinkable.
A água continha impurezas que a tornavam imprópria para beber.
2. Moral or spiritual corruption; lack of purity in character or intentions
He questioned the impurity of her motives.
Ele questionou a impureza de suas intenções.
3. In chemistry or materials science, foreign or undesired substances mixed with a pure substance
The presence of impurities affected the crystal structure.
A presença de impurezas afetou a estrutura do cristal.