'shadowily' originates from the adjective 'shadowy,' which comes from the Old English word 'sceadu,' meaning 'shade' or 'shadow.'

'sceadu' transformed into the Middle English word 'schadowe,' and eventually became the modern English word 'shadowy,' from which 'shadowily' is derived.

Initially, it meant 'shade or darkness,' but over time it evolved into its current meaning of 'in a manner that is dimly lit or obscured by shadows.'