covered with mucus from the nose

You could have told me I had a snotty nose! 你早该告诉我我在流鼻涕！

I don't want to use your snotty handkerchief! 我不想用你这块沾满鼻涕的手帕！

rude and behaving badly, especially by treating other people in a way that shows that you believe yourself to be better than them

I hate having to deal with snotty customers. 我讨厌应付蛮横无理的顾客。

a snotty teenager 举止无礼的少年

She was so snotty to me! 她对我太放肆了！