The post yesterday asking about Ikea components has got me a couple of responses.
Steve Walsh says:
IIRC, they are; threaded pin rod and rotating lock screw
Alex Hudson says:
Your Ikea part isn't; it's a standard fixing based on a traditional dowel wood joint. The dowel is replaced by a cam dowel, which is the upright fixing, and it mates with the cam lock, which is the round thing. They work best where the cam lock has sharp teeth and the hole is tight on the lock, that's the only way the joint stays tight. A traditional dowel joint is usually stronger, and you can replace dowels relatively straightforwardly - a cam lock becomes looser over time, and you can't replace them to tighten them.
Thanks for the responses folks! Most interesting
So it seems the term for this type of fastener is "cam and dowel", though this leads me to think perhaps they are also known as "knock-down fasteners".