1. Occurring every second year
   - biennial 
2. Occurring or payable twice each year
   - semiannual, biannual, half-yearly

1. Every two years
   - biennially 
2. Twice a year
   - semiannually

See also: periodic, periodical

• elasticity of shear
• elasticized
• elastin
• elastomer
• Elastoplast
• elastosis
• elate
• elated
• elatedly
• elater
• elaterid
• elaterid beetle
• Elateridae
• elating
• elation
• elative
• Elavil
• Elbe
• Elbe River
• elbow
• elbow bone
• elbow grease
• elbow joint
• elbow pad
• elbow room