1. plural of planula; free-swimming larval stages of cnidarians (such as jellyfish and corals) that are typically flattened and ciliated
Usage: biology; zoology

Examples

• The planulae swim freely in the water column before settling on a suitable surface.
• Marine biologists collected planulae to study coral reproduction.
• After fertilization, the embryos develop into planulae within a few days.
• The planulae use their cilia to move through the water.
• Scientists observed planulae attaching to rocks on the ocean floor.
• The timing of planulae release varies among different coral species.