Relating to or having a tail where the vertebral column bends upward and extends into the upper lobe, as in many fish.
From Greek hetero- (different, other) plus kerkos (tail). The term describes an asymmetrical tail structure where the backbone extends unequally into the tail.
Fish with heterocercal tails—like sharks and some ancient fish—actually have a physical advantage for swimming, but over evolutionary time, many species 'improved' by developing symmetrical tails instead!
Complete word intelligence in one call. Free tier — 50 lookups/day.