Telethon (noun)

1. A long, continuous television or radio program during which money is raised for charity by taking pledges from members of the public.
2. An event at which a large amount of money is raised for a particular cause or organization, typically by making appeals for donations over the telephone during a broadcast.

Origin:

Mid 20th century: blend of telephone and marathon.

Examples:

1. The annual telethon raised millions of dollars for children's hospitals.
2. The telethon was a huge success, bringing in over $10 million in donations.
3. The telethon was a marathon of fundraising, lasting over 24 hours.
4. The telethon was a way for people to support a good cause.
5. The telethon was an important event for the local community.