In Estonian folk religion, mysterious elves living under the earth.

These small folk had suitably tiny possessions, and their world was differently oriented from the mortal world above them (up was down and right was left). People came in contact with them either by chance or at the elves' wish. Legends tell of distraught elves seeking help from humans in cases of difficult childbirth or illness. A human could marry an elf, but such marriages eventually dissolved. In Finland, such elves were called maahiset.

More on "maa-alused" from the 32 Volume Encyclopædia Britannica:
Search for "maa-alused" at Encyclopædia Britannica Online for all this plus dictionary definitions, magazine articles, and more.
Britannica Concise is a complete, 28,000 article, single-volume encyclopedia from the editors of Encyclopædia Britannica. Visit Encyclopædia Britannica Online to access the complete Encyclopædia Britannica, the Britannica Student Encyclopedia, a world atlas, interactive timelines, Merriam-Webster's Collegiate Dictionary and Thesaurus, hundreds of magazine titles, daily features and much more.