airtime

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