Circumference- The distance around a circle.
Circumnavigate- To sail completely around.
Circumscribe- To determine limits.
Circumspect- Heedful of circumstances around oneself
Circumstance- Condition around of affecting an event.
Circumvent- Avoid by going around
Compassion- Sympathy and willingness to help
Composure- Calmness of the body or mind
Encounter- To meet someone or something unexpectedly
Spontaneous- Something that is unplanned such as a road trip etc.