Had a barium swallow and my stomach didn't empty during the study even after moving the table. what does this mean?

Not enough info : A barium swallow is not the best test to look at stomach motility. If your stomach didn't empty further testing is needed. You should seek evaluation by a gastroenterologist.

Gastroparesis ?: Gastroparesis is slow emptying of the stomach and is caused most commonly by diabetes or medications, though there are many other causes. If you have no symptoms like chronic diarrhea, nausea, vomiting or early satiety, this may not be of any significance for you. It is best to assess this finding in conjunction with your current health with your doctor.

It may mean: nothing. Barium is inert and doesn't stimulate the stomach to empty very well, particularly if you are nervous. However, delayed gastric emptying(gastroparesis) is also a possibility, and this can be due to various etiologies. Talk to your doctor. If you had the study as an outpatient for nonspecific pain, and you are otherwise healthy, it probably doesn't mean anything.