From Wiktionary, the free dictionary
From mid- + swim.
midswim (not comparable)
- During a swim.
2015 August 18, Patrick Heij, “A Roving Manhattan Pool Party Eases the Summer Heat”, in New York Times[1]:At the Hotel Americano, cabanas surround an aquamarine lagoon 10 stories above the city, while a poolside bar awaits midswim margarita orders.
