selena-
combining form
variants or selen-
: containing selenium in place of carbon or regarded as in place of carbon usually in place of the methylene group −CH2−
selenacyclopentadiene
selenazole
compare oxa-, thia- 
Word History
Etymology
International Scientific Vocabulary, from New Latin selenium
- right brain
- right circular cone
- right circular cylinder
- right cylinder
- right down someone's alley
- right face
- right field
- right fielder
- right hand
- right hand of fellowship
- right hands
- right helicoid
- right here
- right honorable
- Right Honourable
- right now
- right of approach
- right of assembly
- right of asylum
- right of center
- right of confrontation
- right of drip
- right of emption
- right of search
- right of sole emption