Definitions for "Tranquillity"
The quality or state of being tranquil; calmness; composure.
A sense of a lack of disturbance from either visual or noise intrusion.
an untroubled state; free from disturbances
Keywords:  quiet, peace
a state of peace and quiet
Keywords:  model, rule, object, activity, level
A security model rule stating that the security level of an active object cannot change during the period of activity.