talk time
1) In customer relationship management (CRM), talk time is the amount of time a call center agent spends with a caller during a transaction. Talk time typically includes everything from "hello" to "goodbye" and is often expressed in terms of average minutes.
2) In wireless telephone service, talk time is the total time a battery can power a phone while the telephone is used to receive or perform a call. Because talk time requires more power, it is much shorter than standby time.