A brownie or broonie (Scots),[1] also known as a brùnaidh or gruagach (Scottish Gaelic), is a household spirit from Scottish folklore that is said to come out at night while the owners of the house are asleep and perform various chores and farming tasks. The human owners of the house must leave a bowl of milk or cream or some other offering for the brownie, usually by the hearth. Brownies are described as easily offended and will leave their homes forever if they feel they have been insulted or in any way taken advantage of. Brownies are characteristically mischievous and are often said to punish or pull pranks on lazy servants. If angered, they are sometimes said to turn malicious, like boggarts.

Brownies originated as domestic tutelary spirits, very similar to the Lares of ancient Roman tradition. Descriptions of brownies vary regionally, but they are usually described as ugly, brown-skinned, and covered in hair. In the oldest stories, they are usually human-sized or larger. In more recent times, they have come to be seen as small and wizened. They are often capable of turning invisible and they sometimes appear in the shapes of animals. They are always either naked or dressed in rags. If a person attempts to present a brownie with clothing or if a person attempts to baptize him, he will leave forever.

Although the name brownie originated as a dialectal word used only in the UK, it has since become the standard term for all such creatures throughout the UK and Ireland. Regional variants in England and Scotland include hobs, silkies, and ùruisgs. Variants outside England and Scotland are the Welsh Bwbach and the Manx Fenodyree. Brownies have also appeared outside of folklore, including in John Milton‘s poem L’Allegro. They became popular in works of children’s literature in the late nineteenth century and continue to appear in works of modern fantasy. The Brownies in the Girl Guides are named after a short story by Juliana Horatia Ewing based on brownie folklore.