"Lawful admission" means that you, being outside the United States, present yourself at a port of entry, are inspected by an officer, do not present fraudulent documents or falsely claim to be a citizen, and are permitted entry by an officer. That's really all there is to it. If you sneak in, present fraudulent documents or lie about your citizenship, or are "paroled" into the country on some basis (e.g. humanitarian reasons pending an application), then you are not admitted even though you are present in the United States.What exactly constitutes "admission"?
That is correct, if you are inadmissible, you should never leave the country if you want to get back in. Depending on the situation, there may be waivers available, but if you leave the country even by stepping over the border line for one second, you have to be admitted back in.For example if one has admitted to an offense that is not deportable but only renders the person inadmissible, does that mean the person should never leave the country for or does it mean that person should never leave for greater than 6 months? Of course assuming the person wants to continue residence in the US.
(The other situation is that just as you can be paroled into the country, you can also get advance parole to leave while an application is pending, in which case while you will have to be inspected to return, you are considered for immigration purposes not to have left, for some purposes.)
It is!I have been given to understand that leaving for a day and returning is an "admission" or is it not?