Rough, careless, or rude; lacking in courtesy or proper care (a na-adjective describing attitude or treatment).
ぞんざいな扱いを受けて怒った。
I was angry at being treated rudely.
文章がぞんざいで意味が取りにくい。
The writing is sloppy and hard to understand.
彼の口調はぞんざいだが、仕事はできる。
His tone is rude, but he can do the job.