To reach (a conclusion) by applying rules of logic or other forms of reasoning to given premises or known facts.
To examine, explain, or record (something) in an orderly manner.
To grasp a concept fully in one's mind, especially (of words, statements, art, etc.) to be aware of the meaning of and (of people) to be aware of the intent of.
To believe, to think one grasps sufficiently despite potentially incomplete knowledge.
To stand underneath, to support.