On Saturday I was pottering around the stone circle at Avebury, which is a bit like Stonehenge but wider and shorter, when somebody asked me what a henge was. I had no idea. Moreover, the powerful spirits of the neolithic gods were interfering with my iPhone so I couldn't find out instantly. A Swedish chap suggested that henge meant stone, which would have made Stonehenge mean stonestone. This would have been fun, but was not true.
Henge relates to hang and to hinge. A hinge is the centre upon which the everything else hangs. A henge-cliff is an overhanging rock and so Stonehenge is the Hanging-Stones. This may be because the horizontal stones hang upon the others, or because the monument could usefully double as a gallows.
Stonehenge has only been called by that name since the twelfth century, before that it was known as the Giant's Dance.
Avebury stone circle has mysterious and powerful properties that cannot be explained by rational thought. For example, when I was standing exactly in the middle of the circle and facing towards the setting sun, I suddenly received two text messages despite the fact that my phone said NO SIGNAL.
The Inky Fool comparing washing powders.
P.S. If anyone can find a video of Flanders and Swann doing the Henge monologue, I would be most grateful.