ra·di·o·nu·clide 
(rā′dē-ō-nklīd′, -ny-)
(rā′dē-ō-nklīd′, -ny-)n.
A radioactive nuclide, especially one used within the body for diagnostic or therapeutic purposes.
- special session
- special team
- special theory of relativity
- specialty
- speciate
- speciation
- speciational
- specie
- species
- speciesism
- speciesist
- species-specific
- species-specificity
- specifiable
- specific
- specifically
- specification
- specific epithet
- specific gravity
- specific heat
- specific humidity
- specific impulse
- specificity
- specific performance
- specific resistance