1. plural of pluteus; free-swimming larval stages of sea urchins and brittle stars
Usage: biology; marine biology

Examples

• The plutei developed from fertilized sea urchin eggs in the laboratory.
• Marine biologists studied the plutei under microscopes to observe their development.
• The plutei eventually metamorphose into adult echinoderms.
• Different species of sea urchins produce distinctly shaped plutei.
• The plutei swim using ciliated bands around their bodies.