Definitions
1.VerbTo know the meaning of; to parse or have parsed correctly; to comprehend."Can you repeat what you just said? I didn't understand."
2.VerbTo know the meaning of.
3.VerbTo be thoroughly familiar with; to be able to undertake properly."The students understood the assignment."
4.VerbTo comprehend a fact or principle; to regard or come to regard a belief as such."I understand that company policy says I can't get a refund, but can you make an exception?; There's been no formal declaration, but it's understood that a state of war exists between the two countries"
5.VerbTo know the intent, motives or character of; to know the causes of or reasons for."One day you say you love me, the next you ignore me—I don't understand you!"
6.VerbTo believe or infer, to think one grasps sufficiently despite potentially incomplete knowledge."I've been given to understand that you have a package for me?; At least four people are understood to have been injured."
7.VerbTo regard as present when not."In the imperative mood, the word “you” is usually understood."
8.VerbTo stand underneath, to support.
9.InterjectionUh-huh, I see; a way to acknowledge something said by the other speaker.