Is "光轮" for "Nimbus" as in "Nimbus 2000 broomstick" just a transliteration?
光轮 is not a transliteration, it is a translation

Halo (religious iconography)
A halo (from Greek ἅλως, halōs;1 also known as a nimbus, aureole

The round thing behind Buddha's head on that page is a 光轮 or 光环