Wiktionary(0.00 / 0 votes)Rate this definition: mutant(Noun) Something which has mutated, which has one or more new characteristics from a mutation. mutant(Noun) Someone or something that seems strange, abnormal, or bizarre. mutant(Adjective) That has undergone mutation.
Best Answer: The Blue Whale, Balaenoptera musculus, is the largest mammal living today. It is also the largest mammal to have ever lived. In fact the Blue whale is the largest animal ever to have lived on the planet as far as we know; bigger by far than ever the largest Dinosaur.
For over a century, Paraceratherium â a 26-foot-long, 15 ton, hornless rhino â has been cited as the biggest of the big beasts. But, according to a new paper by Asier Larramendi, ancient elephants are in close competition for the title of the largest mammals to ever walk the Earth. Such contests rely on how theyâre measured, of course. Part of what makes Paraceratherium seem so large is its elongated neck.