From Longman Dictionary of Contemporary Englishhelplinehelp‧line /ˈhelplaɪn/ noun [countable] TCTa telephone number that you can ring if you need advice or information
Examples from the Corpus
helpline• Now the county's Police Federation has set up a helpline to give advice to officers facing complaints.• Although we were officially the London helpline, we got calls from all over Britain and from all over the world.• Mr. Golding I repeat: where do people find out that the helpline exists and obtain the number?• The helpline for former pupils, staff and parents is producing vital new information.• The helpline is for both authorities. 