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.
Passionate about all things Australian. The largest mammal is the Blue Whale, not only the largest living but also the largest of all time. It may weigh between 110 and 160 tonnes. It is followed by (in order) the North Pacific Right Whale, the Sperm whale, Baird's beaked whale and then the Orca.