melon melonlipid-filled sac in the forehead of whales that helps to focus sound Related Articles: Glossary: click trainHow do marine mammals produce sounds?Featured Sound: Beluga WhaleHearing in Cetaceans and Sirenians, the Fully Aquatic EarHow did odontocete hearing evolve?Beluga Whale, White WhaleSonarCommon DolphinMelon-headed whalePilot Whale Chris Knowlton2017-02-26T20:09:59-05:00