In a manner relating to or characteristic of an aurora; in the way auroras behave or appear.
From auroral (Latin aurora + -al) plus -ly adverb suffix. This is an extremely rare adverb, likely appearing only in poetic or highly specialized atmospheric science contexts.
Aurorally is so uncommon that it barely qualifies as a real word—you'd probably never hear it outside of poetry trying to describe lights that shimmer like the northern lights.
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