SINCE 1828
radi-
combining form
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
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