verb

• (transitive) (of words, statements, art, etc.) To know the meaning of.
• (transitive) (of people) To know the intent, motives or nature of or (of events) to know the causes of or reasons for.
• To believe, to think one grasps sufficiently despite potentially incomplete knowledge.
• (humorous, rare, obsolete outside circus, acrobatics) To stand underneath, to support.