1. A radioactive metallic element that is similar to tellurium and bismuth; occurs in uranium ores but can be produced by bombarding bismuth with neutrons in a nuclear reactor
   - polonium, Po

Type of: metal, metallic element

• genus Carpocapsa
• genus Carpodacus
• genus Carthamus
• genus Carum
• genus Carya
• genus Caryocar
• genus Caryota
• genus Casmerodius
• genus Cassia
• genus Cassiope
• genus Castanea
• genus Castanopsis
• genus Castanospermum
• genus Castilleia
• genus Castilleja
• genus Castor
• genus Castoroides
• genus Casuarina
• genus Casuarius
• genus Catacala
• genus Catalpa
• genus Catananche
• genus Catasetum
• genus Catha
• genus Catharacta