IPA: /ˈʃædoʊləs/
KK: /ˈʃædoʊləs/
Not having a shadow or the ability to cast one.
The bright light made the object appear shadowless.
Shadowless → It is formed from "shadow" (from Old English *sceadu*, meaning shade or shadow) and "-less" (meaning without). The word "shadowless" means without a shadow or lacking shade.
Think of being 'without' ('-less') a 'shadow' ('sceadu') — that's why shadowless means lacking a shadow.