RADIO is a playable word

radio Scrabble® Dictionary

verb
radioed, radioing, radios or radioes
to transmit by radio (an apparatus for wireless communication)
29 Playable Words can be made from "RADIO"
   2-Letter Words (9 found)
   3-Letter Words (13 found)
   4-Letter Words (5 found)
   5-Letter Words (2 found)