1 a : direct observation of or participation in events as a basis of knowledge
b : the fact or state of having been affected by or gained knowledge through direct observation or participation
2 a : practical knowledge, skill, or practice derived from direct observation of or participation in events or in a particular activity
b : the length of such participation has 10 years' experience in the job
3 : something personally encountered, undergone, or lived through
4 a : the conscious events that make up an individual life
b : the events that make up the conscious past of a community or nation or humankind generally
5 : the act or process of directly perceiving events or reality