noun

1. A state of being away or withdrawn from a place or from companionship; the period of being away.

   "Absence makes the heart grow fonder."

2. Failure to be present where one is expected, wanted, or needed; nonattendance; deficiency.

3. Lack; deficiency; nonexistence.

   "He had an absence of enthusiasm."

4. Inattention to things present; abstraction (of mind).

   "absence of mind"

5. Temporary loss or disruption of consciousness, with sudden onset and recovery, and common in epilepsy.

6. Lack of contact between blades.