Definition of «marathoner»

A marathoner is a person who runs long-distance races called marathons.

As with marathoners who don't plan, the odds of failure are going to be significantly higher for people opting to wing it. (canadianbusiness.com)
Robbie also coaches ultra marathoners remotely. (blog.feedspot.com)
These people were in great shape; they ran like marathoners and napped like lords. (discovermagazine.com)
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