What Does Mild Adenoidal Hypertrophy Mean?

Hi My son is 7 years of age and always has a running nose. When he sneezes there is so much that comes out it is not funny. We have had a xray done and it has showed up that he has Mild adnenoidal hyperyrophy that is present. Can you please explain what this is and what is the best option to take to help this situation. Thanks