Understanding a concept means you get it. If there is understanding between people, they are friendly towards each other and trust each other. The meaning of understanding is a mental grasp :
Truth is finally out about Trump HBCU Sports Forums
To be understanding is to be sympathetic to someone’s woes. Understanding first published thu may 6, 2021 understanding is a protean concept in philosophy, and the desire for understanding is pervasive in everyday life. Understanding implies abilities and dispositions with respect to an object of knowledge that are sufficient to support.
Or about how something works:
Understanding is a relation between the knower and an object of understanding. Mental process of a person who comprehends; Find 224 different ways to say understanding, along with antonyms, related words, and example sentences at thesaurus.com. Definition of understanding noun in oxford advanced learner's dictionary.
Comprehension —usually used with of. Knowledge about a subject, situation, etc. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. See examples of understanding used in a sentence.
Your understanding might be that your mother will always drive you to school if you miss the bus.
You cannot use comprehension with this meaning. How to use understanding in a sentence.