ANNOTATION:
A Technical Definition and Math URL

MEME. Noun. A memory item, or portion of an organism’s neurally-stored information, identified using the abstraction system of the observer, whose instantiation depended critically on causation by prior instantiation of the same memory item in one or more other organisms’ nervous systems. ("Sameness" of memory items is determined with respect to the above-mentioned abstraction system of the observer.)

I have also published a less technical memetics book, Thought Contagion, with information at http://www.mcs.net/~aaron/thoughtcontagion.html.

--Aaron Lynch