variants: or radio-

Definition of radi-

1 : radiant energy : radiation radioactive radiopaque
2 : radioactive radioelement
3 : radium : X-rays radiotherapy
4 : radioactive isotopes especially as produced artificially radiocarbon
5 : radio radiotelegraphy
6 : radius bone radio-ulna

History and Etymology for radi-

French, from Latin radius ray

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