The coat has got oil stains on it.

衣服油了。

《新英汉大辞典》

A western grebe wears a fatal coat of oil from a spill off California in 1969.

1969年加利福尼亚海岸石油外漏，西部䴙䴘身披致命的原油外衣。

youdao

If it does, she said, people shouldn’t expect oil to coat Atlantic beaches and wildlife. That’s because some oil will evaporate, be eaten by microbes, and become diluted in sea water.

她说：如果油污最终抵达大西洋，人们不必担心大西洋海滨会被原油覆盖，或野生动物遭到涂炭，因为油污会蒸发一部分，被微生物分解一部分，及被海水稀释一部分。

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After about a minute, add about 2 teaspoons of the olive oil and swirl to coat the pan.

NPR: Vegetables with Flair for the Thanksgiving Plate

Add the remaining olive oil and swirl to coat the pan.

NPR: Vegetables with Flair for the Thanksgiving Plate

When cooking the fish skin-side down, be sure to coat the pan completely with oil, and to watch the fillet closely.

WSJ: Tyson Cole's Branzino With Herbs, Tomatoes and Thai Chilies | Slow Food Fast