na-adjective
rough; careless; slipshod; rude
Describes actions, work, or speech that are done without proper care or respect, often implying a lack of refinement or politeness. Can refer to both physical carelessness and interpersonal rudeness.
彼の仕事はいつもぞんざいで、ミスが多い。
His work is always slipshod, with many mistakes.
客に対してぞんざいな口をきくな。
Don't speak rudely to customers.