1. plural of fucoid; brown algae or seaweeds belonging to the class Phaeophyceae, characterized by the presence of a brown pigment (fucoxanthin) in addition to chlorophyll.
Usage: technical/scientific; plural form
2. organisms or fossils resembling or related to brown algae; used in paleontology and geology to describe trace fossils or sedimentary structures.
Usage: paleontology; geology; technical

Examples

• The rocky shore was covered with various fucoids clinging to the rocks.
• Marine biologists collected samples of fucoids to study their adaptation to tidal zones.
• Fucoids are an important food source for many coastal herbivores.
• The fossil record contains numerous fucoids that help scientists understand ancient marine environments.
• Kelp and bladder wrack are common examples of fucoids found in temperate waters.