Entry 1 sense Webster, 1913 Bubble shell /bŭb'-əl shĕl/ · Bub·ble shell · IPA 01 A marine univalve shell of the genus Bulla and allied genera, belonging to the Tectibranchiata. 1. A marine univalve shell of the genus Bulla and allied genera, belonging to the Tectibranchiata.(Zool.)