An accident is an unforeseen incident. Example: A car crash with another car would be an accident and if you were to get into a fight with the driver of the other car, that would be an incident. The car crash is the accident and the fight with the other driver would be an incident. Accident: a. An unexpected and undesirable event, especially one resulting in damage or harm: b. An unforeseen incident: A series of happy accidents led to his promotion. c. An instance of involuntary urination or defecation in one's clothing. 2. Lack of intention; chance: ran into an old friend by accident. Incident: 1. A definite and separate occurrence; an event. 2. A usually minor event or condition that is subordinate to another. 3. Something contingent on or related to something else. 4. An occurrence or event that interrupts normal procedure or precipitates a crisis: an international incident. adj. 1. Tending to arise or occur as a result or accompaniment: 2. Related to or dependent on another thing. 3. Physics Falling upon or striking a surface: incident radiation. http://www.thefreedictionary.com/incident

incident means an individual occurrence or event. accident means an undesirable or unfortunate happening that occurs unintentionally and usually results in harm, injury, damage, or loss; casualty; mishap: automobile accidents.

accident means when smth happened and cause some harm.(car crash) incident means smth unpleasant but without any harm(unpleasant situation)