輻射[fukusha] radiation
輻射点[fukushaten] radiant point
輻湊[fukusou] congestion (e.g. traffic)
輻射線[fukushasen] radiation
輻射熱[fukushanetsu] radiant heat

輻射エネルギー[fukushaenerugii] radiant energy
制動輻射[seidoufukusha] bremsstrahlung (physics)
トラフィック輻輳[torafikkufukusou] traffic congestion
ポート輻輳[pootofukusou] port congestion