What is the definition or description of: syncope?

Passing out: Or loss of consciousness.

Fainting: Syncope results from decreased blood flow to brain due to cardiac problems, hypotension, anemia, vasovagal reactions (sight of blood, foul aromas, etc), dehydration. Starts with light-headedness, narrowing and darkening of vision, malaise. Then loss of consciousness for a few seconds, and arousal without confusion but nausea, chills, sweating.

Fainting : Loss of consciousness and postural tone caused by diminished cerebral blood flow. Syncope may indicate a particular medical condition, however often it may occur in an otherwise healthy individual. It is a common problem, accounting for 3% of emergency room visits.