oil and water
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oil and water
Two objects, elements, factors, forces, people, etc., that do not or cannot mix together readily. (Usually used comparatively, as in "X and Y are like/as oil and water.") Refers to the natural tendency of oil and water to separate. My dad is like oil and water with my mom's boyfriend, so I don't know how they're going to get through the family reunion in each other's company. The more I pay attention to the news, the more it seems that politics and common sense are as compatible as oil and water.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
oil and wateror
like oil and water
If two things or people are oil and water or are like oil and water, they are very different and they cannot exist together or be mixed with each other successfully. He'd known from the start that Nick and Adam would never mix. They were like oil and water. I tried to make both my parents part of my life but they were oil and water and refused to be mixed. Like oil and water, the worlds of work and pleasure do not blend easily.
Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012
oil and watertwo elements, factors, or people that do not agree or blend together.
Water and oil are two liquid substances that repel each other and cannot be mixed together.
Farlex Partner Idioms Dictionary © Farlex 2017