ballyhoo: [20] Ballyhoo remains an etymological mystery, but there is no shortage of suggested candidates as its source: an Irish village called Ballyhooly; an old nautical slang word ballyhoo meaning ‘unseaworthy vessel’, which seems to have been an anglicization of Spanish balahú ‘schooner’; and the bizarre late- 19th-century ballyhoo bird, a fake bird made of wood and cardboard and intended to fool a birdhunter. None of them, alas, seems remotely relevant to ballyhoo’s original American sense, ‘barker’s patter outside a circus tent, to encourage people to enter’.
"publicity, hype," 1908, from circus slang, "a short sample of a sideshow" (1901), which is of unknown origin. There is a village of Ballyhooly in County Cork, Ireland. In nautical lingo, ballahou or ballahoo (1867, perhaps 1836) meant "an ungainly vessel," from Spanish balahu "schooner."