Knowledge about a subject, situation, etc. Comprehension usually used with of. The meaning of understanding is a mental grasp :
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Understanding is a relation between the knower and an object of understanding. Understanding implies abilities and dispositions with respect to an object. He noted bond's apparent lack of.
Both comprehension and understanding can be used to talk about someone's ability to understand something.
Understanding a concept means you get it. How to use understanding in a sentence. Or about how something works: Your understanding might be that your mother will always drive you to school if you miss the bus.
