Hi,

It comes from the gaelige "seisiu/n" which according to my dictionary translates as "session"(!!?!)

I have always taken it to mean where a few (or as many as you like) performers have got together with a common purpose.. in this case to play Irish music. Don't you call them "jam sessions" in the US? (where people get together just to make music and have a bit of craic?(meaning, fun, good company etc...))

slainte

alison