Early 19th century (in an earlier sense). From sub- + radius. In sense 1 probably after post-classical Latin subradius. In sense 2 after German Subradius.
Definition of subradius in US English:
subradius
nounˌsʌbˈreɪdɪəs
Entomology= radial sector. rare. Now historical.
Origin
Early 19th century (in an earlier sense). From sub- + radius. In sense 1 probably after post-classical Latin subradius. In sense 2 after German Subradius.