phone-in
/ˈfəʊnɪn/noun
1- a radio or television programme during which the listeners or viewers telephone the studio and participate（电台听众, 电视观众）热线参与节目。
1.1
- as modifier denoting something conducted by people leaving answers or messages by telephone通过电话进行的：
a phone-in contest
热线竞答
a phone-in poll.
电话民意测验。