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.
The blue whale (Balaenoptera musculus) is a marine mammal belonging to the baleen whales (Mysticeti). At up to 29.9 metres (98 ft) in length and with a maximum recorded weight of 173 tonnes (191 short tons) and probably reaching over 181 tonnes (200 short tons), it is the largest animal known to have ever existed.