A ghostly shadow is an example of an amorphous shadow.
Glass is an amorphous material.
Origin of amorphous
- From Greek amorphos a- without a–1 morphē shape
From American Heritage Dictionary of the English Language, 5th Edition
- From Ancient Greek ἄμορφος (amorphos) "without form, shapeless, deformed" (itself from α- (a-) "without" + μορφή (morphē) "form") + the English suffix -ous