The origins of sean-nós singing are unknown, but the style is certainly hundreds of years old.
The term sean-nós, which simply means 'in the old way', is a vague term that can also refer to various other traditional activities, musical and non-musical. The style covers a range of genres, from love song to lament to lullaby, traditionally with a strong focus on conveying the relevant emotion of the given song.
Sean-nós singing usually involves very long melodic phrases with highly ornamented and melismatic melodic lines, differing greatly from traditional folk singing elsewhere in the British Isles. Sean-nós ( / ˈ ʃ æ n oʊ s/ SHAN-ohss, Irish: Irish for 'old style') is a term referring to a style of unaccompanied traditional Irish vocal music usually performed in the Irish language.