1st_ In Spain it is a way to call a young lover (or suitor) of a mature woman, also if intended by her. Its use is between mockery and affection. I'm sure it comes from yogurt, possibly because "it's not curdled"; something similar to its synonym petit-suisse. See toy boy, milf. 2nd_ By the above meaning is also any teenager, and in this case can be used in feminine as 'yogurt' .
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