gainer

plural gainers

1. One who gains a profit or advantage.

   Let every youth take a leaf out of my book and make it a point to account for everything that comes into and goes out of his pocket, and like me he is sure to be a gainer in the end.

   1925-29, Mahadev Desai (translator), M.K. Gandhi, The Story of My Experiments with Truth, Part I, chapter xvi

   2 more examples

   … it is obvious that the Californian heiress is not the only gainer by an alliance which will enable her to make the easy and common transition from a Republican lady to a British peeress.

   1892, Sir Arthur Conan Doyle, “The Noble Bachelor”, in The Adventures of Sherlock Holmes, HTML edition, The Gutenberg Project, published 2011

   Thus, after eighteen months of fantastic and ruinous warfare, the companies had come to their senses and agreed to do what they might have done at the start; the only gainers were the passengers who had been carried at ridiculously uneconomic fares.

   1956 January, M. D. Greville, “Scottish Railways in 1856”, in Railway Magazine, page 53

2. One who puts on weight.
3. slangdivingA diving or gymnastics maneuver, from a high diving board or platform, involving a simultaneous inversion and rotation.

   Wiener went up so fast it did a gainer.

   2015, David Spade, Almost Interesting: The Memoir, HarperCollins, →ISBN

   1 more example

   I tried a full gainer with a twist, the way he did it, but succeeded only in smacking the water with my thighs.

   1961, Stanisław Lem, chapter 4, in Return from the Stars

plural Gainers

1. A surname.