Elf-cup

Elf-cups; All terrestrial species; all seasons; (poor eating of themselves).

Source: wiktionary

Many toadstools are dainty enough to deserve their popular names: "Pixies' parasols," "Fairies' bath," "Elf cups," and so on.

Source: wiktionary

HOLY-STAAN, A stone with a natural hole in it, which was frequently suspended by a string from the tester of a bed, or from the roof of a cow house, as an infallible prevention of injury from witches!! In Scotland these stones are called elf-cups.

Source: wiktionary

Elf cups are often found in Sweden on the covering blocks of our dolmens. The dolmens belong in Sweden exclusively to the Stone-age, but I am not quite sure if the cup-marks on them can be ascribed to so high an antiquity. The cup-bearing blocks could be visible in other prehistoric periods as they are to-day, and in that way they do not necessarily belong to the times of erection of the dolmen itself.

Source: wiktionary