What does it mean when one of your tonsils are swollen?

It could be strep throat and if it happens more often than not, consider talking to a doctor about removing them. The tonsils combat bacteria and viruses that enter your body through your mouth. However, tonsils are also vulnerable to infection from these invaders. Tonsillitis can be caused by a virus, such as the common cold, or by a bacterial infection, such as, like i said, strep throat.