night line
/ˈnʌɪt lʌɪn/noun
1 Angling. A line with baited hooks set to catch fish at night.
2Chiefly British. Usually in form Nightline. A telephone helpline available at night, especially for university or college students (frequently as the name of such a service); (hence more widely) any overnight out-of-hours telephone service.
Origin
Early 18th century; earliest use found in Gentleman Angler. From night + line.