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