The Collaborative International Dictionary of English v.0.48:

Radiotelegraphic \Ra`di*o*tel`e*graph"ic\
   (r[=a]`d[i^]*[o^]*t[e^]l`[-e]*gr[a^]f"[i^]k), a.
   Of or pertaining to radiotelegraphy; employing, or used or
   employed in, radiotelegraphy.
   [Webster 1913 Suppl.]