apotropaic (adj.): Having or reputed to have the power of averting evil influence or ill luck.
I found this great word in Magistra et Mater’s report on a recent IHR seminar by Annette Kehnel, here. I recommend it to you (the post that is, not just the word) together with many other interesting posts to be found there.
In this report Magistra discusses Annette’s paper which examined the role of humility/humiliation in ritual behaviour during medieval royal inaugurations. I was particularly struck by the suggested apotropaic use of such rituals in political display and the way in which looking at ritual this way seems to demand a collapse of the humility/humiliation distinction. Presumably the voluntary humiliation of a public figure, such as in the cited example of kings of Ulster reportedly mating with a white mare, would, in this light, be part of what protects him/her from later criticisms of pride, of acting without church/community/peer authorization, and so forth. But is humbling oneself, for instance, by bowing the head before an archbishop, really the same as being humiliated?
What do you think? Are they the same or different? And does it matter for the proposed evil-averting intention of the ritual?
 Oxford English Dictionary <http://www.oed.com.ezp.lib.unimelb.edu.au/view/Entry/9475?redirectedFrom=apotropaic#eid> [accessed 28 February 2013].
Warning! Gerald of Wales reference! There may be serious questions over whether such ritual activity can or should be taken as given… There is also the question of whether, assuming Gerald’s report stands, we should also assume such behaviour was considered humiliating in an early medieval Irish context… But I digress.