round-tripswimmer
nounUK /ˌraʊnd ˈtrɪp ˌswɪmə/
US /ˌraʊnd ˈtrɪp ˌswɪmər/
A round-trip swimmer is a person who swims to a place and then swims back.
The round-tripswimmer crossed the lake and returned to the same beach before lunch.
OTHER MEANINGS
2. A swimmer who completes a there-and-back crossing of a channel or strait.
Only a few round-tripswimmers have ever crossed the strait in both directions.
3. A person who swims a pool length and back as a single set.
The coach told the round-tripswimmer to do ten easy laps to warm up.
4. A fictional or playful term for someone who keeps returning to the same swimming spot.
Every summer, the old round-tripswimmer showed up at the pier at dawn.