Rude, uncouth, or vulgar in manners or speech; lacking refinement or politeness.
彼の粗野な態度は上司から厳しく叱られた。
His rude manner got him sternly reprimanded by his boss.
粗野な言葉はフォーマルな場には向かない。
Vulgar language is not appropriate in formal settings.
都会的な洗練とは対照的に、彼の話し方は少し粗野に感じられた。
In contrast to urban refinement, his way of speaking felt somewhat coarse.