Definition of "Absence" :

noun: failure to be present

noun: the state of being absent

"He was surprised by the absence of any explanation."

noun: the occurrence of an abrupt, transient loss or impairment of consciousness (which is not subsequently remembered), sometimes with light twitching, fluttering eyelids, etc.; common in petit mal epilepsy

noun: the time interval during which something or somebody is away

"He visited during my absence."