Definition of "quaaltagh"

On these occasions a person of dark complexion always enters first, as a light haired male or female is deemed unlucky to be a first-foot or quaaltagh on New Year's morning. The actors of the quaaltagh do not assume fantastic habiliments like the Mummers of England or the Guisards of Scotland, nor do they, like these rude performers of the ancient mysteries, appear ever to have been attended by minstrels playing on different kinds of musical instruments.

1845, Joseph Train, “Manners and Customs”, in An Historical and Statistical Account of the Isle of Man, from the Earliest Times to the Present Date; […], volume II, Douglas, Isle of Man: […] Mary A. Quiggin, […]; London: Simpkin, Marshall, & Co., […], page 115

On New Year's Eve there occurred an incident which greatly increased the tension at Claddagh House. Mrs. Colquitt was in a painful state of agitation about the quaaltagh, or first person who should cross the threshold after midnight. If he happened to be dark, she anticipated some wonderful slice of luck; if light, a continuance of misfortune; and if a spaagaght or splay-footed person, nothing short of a calamity. […] [S]he kept trotting up and downstairs, being imperatively urged to confide to Mona her wish that the quaaltagh might be somebody she had just thought of, a different somebody each time.

1887, Hugh Coleman Davidson, “Suspense”, in The Green Hills by the Sea: A Manx Story […], volume III, London: Hurst and Blackett, […], pages 4–5

The "White Boys," the "Hunt the Wren Boys," and "Quaaltaghs" received the dessert.

1911, John Clague, Cooinaghtyn Manninagh: Manx Reminiscences, Castletown, Isle of Man: M. J. Backwell, page 11

Did you ever use to go as the ‘quaaltagh?’ […] I did indeed!

1977, Jennifer Kewley Draskau, quoting John Gell, “Verbs”, in Practical Manx, Liverpool: Liverpool University Press, published 2008, page 126