radi-

combining form

variants or radio-
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

Word History

Etymology

French, from Latin radius ray

Dictionary Entries Near radi-

Radetzky

radi-

radiac

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Cite this Entry

“Radi-.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/radi-. Accessed 1 Dec. 2024.

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