The phrase "swimsuit costumes" refers to clothing that people wear at the beach or pool for swimming or sunbathing. It typically includes bathing suits or swimwear. Full definition
Tecmo Koei has released a ton of screenshots looking at exclusive swimsuit costumes for Dead or Alive 5 Ultimate. (justpushstart.com)
As a final treat for fans, the Ultimate Edition contains an exclusive blue swimsuit costume not available in any other edition (gonintendo.com)
The Ultimate Edition also includes all content exclusive to backers of the game from its 2013 Kickstarter campaign, and an exclusive blue swimsuit costume not available in any other edition. (consoleob.com)