airtime

Short definition from Wiktionary

Noun

1. 1
   The duration during which a radio or television program (or part of one) is transmitted.
2. 2
   The duration spent talking during a conversation.
3. 3
   The chargeable use of a mobile phone, either in minutes or in units dependent on the use or traffic.
4. 4
   The period of freefall after jumping.
5. 5
   The period during which a person riding a rollercoaster or similar ride experiences a feeling of weightlessness.