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

• semilunar cartilage
• semilunar valve
• semimajor axis
• semiminor axis
• semimonthly
• seminal
• seminal duct
• seminal fluid
• seminal vesicle
• seminar
• seminarian
• seminarist
• seminary
• seminate
• seminiferous
• seminiferous tubule
• Seminole
• Seminole bread
• seminoma
• seminude
• semiofficial
• semiology
• semiopaque
• semiotic
• semiotical