A genus of marine animals that bear polyps and produce medusae, and that form colonies that attach to rocks or the ocean bottom.
- ‘This is a slide of Obelia, a colonial marine cnidarian that shows a distinct polymorphism in the organization of its members.’
- ‘This slide shows a medusa from the colonial cnidarian Obelia.’
- ‘Although most of the life of Obelia is spent in the sessile polyp form, medusa buds produced within reproductive polyps called gonangia escape into the water column.’
Modern Latin, from Greek obelos tapering column.