On the term 'ceilidh' in relation to English dance/song events - I believe you will find the word in the sleeve notes of the ancient EFDSS/HMV L.P. 'Jug of Punch' where it is used to describe the informal musical gatherings of young people, post-skiffle, circa 1959/1960. The album itself (a belter, as it happens) includes English, Irish and Scots performers -among them Shirley Collins, Seamus Ennis, Isabel Sutherland et al. Ah, the good old days ...