1. a sea urchin
Usage: zoological
2. a rounded molding beneath the abacus of a Doric or Ionic capital
Usage: architectural

Examples

• The echinus rolled along the ocean floor with its spiny exterior.
• Marine biologists studied the echinus population in the tide pools.
• The ancient Greek column featured a beautifully carved echinus.
• The architect pointed out the echinus molding on the temple’s capital.
• Divers observed colorful echinus species among the coral reefs.
• The classical building’s echinus showed signs of weathering over time.