Definitions

1. noun

a large or impressive event, project, or undertaking

“The charity marathon was a huge thon that raised millions of dollars.”

2. noun

a long, grueling physical activity or competition, especially a long-distance run

“The ultra-marathon was a grueling thon that tested the runners’ endurance.”

3. noun

a long or continuous period of time

“The thon of waiting in line was unbearable.”

4. verb

to participate in or complete a long or grueling physical activity

“She thoned the marathon and finished in first place.”