Baird's beaked whale is a large, slender whale with a long, cylindrical beak and a bulbous forehead (melon). Its body is typically blue-grey to black on top and light grey underneath, with a small, triangular dorsal fin located about two-thirds of the way down its back. Both sexes have two pairs of large, triangular teeth on the lower jaw that erupt when sexually mature, with males having more prominent scarring from male-to-male encounters.