Classifications of fairies

The fairies of Irish, English and Scottish folklore have been classified in a variety of ways. Two of the most prominent categories, derived from Scottish folklore, are the division into the Seelie Court and the Unseelie Court.

These categories may reflect an earlier (medieval) classification of the Germanic elves (Dökkálfar and Ljósálfar), as the corresponding Insular Celtic "fair folk" do not appear to have a comparable division. William Butler Yeats, in Irish Fairy and Folk Tales, further divided them into the Trooping Fairies (appearing in splendid processions) and the Solitary Fairies (mischievous spirits appearing on their own). Katharine Mary Briggs noted that a third distinction might be needed for "domesticated fairies" who live in human households (see household spirit).

The Northern and Middle English word seely (also seily, seelie and sealy), and the Scots form seilie, meaning "happy", "lucky" or "blessed" and unseely meaning "unhappy", "misfortunate" or "unholy" are derived from the Old English sǣl and gesǣlig. The Modern Standard English word silly is also derived from this root and the term "seely" is recorded in numerous works of Middle English literature such as those by Geoffrey Chaucer. Many ballads and tales tell of "Seilie wichts";. a Lowland Scots term for fairies. In Wales there were said to be two fairies or elves called Silly Frit and Sili go Dwt whose names represent a borrowing of the adjective silly (in this case meaning happy) as applied to fantastical beings from its usage on the English marches bordering Wales rather than the Anglo-Scottish border; the former name being purely English while the latter is a corruption of English fairy names featuring "tot" (such as Tom Tit Tot) as an element.

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