Definition of basilosaurus in US English:



  • A large marine cetacean of the Eocene epoch, having a long, slender body and vestigial fore and hind limbs. Fossils were discovered in the early 1990s.

    Genus Basilosaurus, suborder Archaeoceti, order Cetacea

    • ‘The first of the truly gigantic whales, Basilosaurus had the serpentine shape of a sea monster and short, sharp teeth for hunting sharks and other prey.’
    • ‘Although Basilosaurus possessed a fluke and peduncle, Buchholtz dismisses these features because they are too short relative to body length.’
    • ‘Then they found tiny legs on a 50-foot long, 40-million year old whale named Basilosaurus.’
    • ‘One of these was pictured in the exhibition - the Basilosaurus.’
    • ‘In Basilosaurus, nearly all of these structures lay within the body wall, and most parts were immobile.’


Modern Latin, from Greek basileus ‘king’ + sauros ‘lizard’.