A dip can be one of many things. As a verb, you dip something by lowering it briefly into a liquid, for example the person in the picture is dipping some bread. The semi-liquid food he is dipping the bread into is also called a dip. Dips are very tasty, can be made from virtually anything, and are usually served with some kind of bread. Many dips are made with a yoghurt base.
A dip is also a shallow dent or depression in the ground, often seen where a drain crosses a road.
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You flip something when you quickly turn it over, either half-way over so it is upside down or flipped over all the way so it comes back to where it was to start with. The boy in the picture is doing a backflip.
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