Those biscuits you used to eat when you were a kid, and you were amazed to stumble upon some re-packaged in the super market the other day when you were all grown up or find in your friends cupboard. Famous ones include the'nice' biscuits which were anything but nice, the ring shaped biscuits with multi coloured icing on that make your teeth itch and look like some acid trip induced creation from the 60's (and still do! including pink and brown colours!) and such things as Bourbons and custard creams can be considered 'retro'
"John, check out the retro biscuits Chris has in his cupboard"