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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Dictionary Entries near radi-

rade

raden

Radetzky

radi-

radiac

radial

radial arm

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to make faulty or ineffective

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