Allan C. - I know niddy-noddy as a Scots word, meaning pretty much what it sounds like! As a spinner's term, I've only seen it in the US. A niddy-noddy is a stick, with a cross piece at each end. The cross pieces are at right angles to each other, and the nid-nod pattern used when skeining the yarn, is what gives the niddy-noddy its name.