gnu: large African antelope having a head with horns like an ox and a long tufted tail
antelope: graceful Old World ruminant with long legs and horns directed upward and backward; includes gazelles; springboks; impalas; addax; gerenuks; blackbucks; dik-diks
relaxation: a method of solving simultaneous equations by guessing a solution and then reducing the errors that result by successive approximations until all the errors are less than some specified amount