I love the shade and the shadow, and would be alone with my thoughts when I may.
—Dracula in Bram Stoker’s eponymous novel.
Shade and shadow. Different or same? Similar? How?
Fowler’s admits they have an almost identical meaning which branches out into a considerable diversity of idiom. Well put, if hardly illuminating. But his mnemonic “clue” to their difference does enlighten.
shade, shadow, nn. The details of this diversity are too many to be catalogued here, but it is a sort of clue to remember that shadow is a piece of shade, related to it as, e.g., pool to water.
So shade fills a shadow to the brim and no farther, and while shadow belongs to a concrete object, shade belongs to the world.
The pool-water analogy is not as trifling as it seems. It’s almost poetic.