What does a swollen lymph node on your collar bone mean?

Most likely...: It means that your body is fighting off an infection. If it doesn't resolve, continues to grow, or becomes painful, see your doctor.

Swollen lymphnodes: In the supraclavicular region ( collar bone ) needs to be evaluated as they may be signs of serious condition . Please see your doc

Monitoring Centers: Lymphatic system absorbs/carries things too big to go into the arteries/veins like bacteria eaten by white cells and digested food. Lymph nodes "taste" the lymph for anything bad like bacteria/viruses/cancers, etc. When it detects a problem, it alerts the immune system and your body reacts. They enlarge in response to the inflammation they create when they react. They shrink when all is well.