IPA: /ˌreɪdiəʊˈdʒɛnɪk/
KK: /reɪdiəʊˈdʒɛnɪk/
Related to or caused by the emission of radiation, especially from radioactive materials.
The radiogenic heat from the Earth's core contributes to volcanic activity.
Radiogenic → It is formed from "radio-" (from Latin "radius", meaning ray) and "genic" (from Greek "genes", meaning born of or produced by). The word "radiogenic" refers to something that is produced by or originating from rays, particularly in the context of radiation.
Think of 'rays' ('radio-') that are 'producing' something ('genic') — that's why radiogenic means something that comes from rays.