meme, memetic

The word was originally coined by Richard Dawkins in his book The Selfish Gene. Here's his definition, along with the logic behind the choice of word.

We need a name for the new replicator, a noun that conveys the idea of a unit of cultural transmission, or a unit of imitation. ‘Mimeme’ comes from a suitable Greek root, but I want a monosyllable that sounds a bit like ‘gene’. I hope my classicist friends will forgive me if I abbreviate mimeme to meme. If it is any consolation, it could alternatively be thought of as being related to ‘memory’, or to the French word même. It should be pronounced to rhyme with ‘cream’.

Examples of memes are tunes, ideas, catch-phrases, clothes fashions, ways of making pots or of building arches. Just as genes propagate themselves in the gene pool by leaping from body to body via sperms or eggs, so memes propagate themselves in the meme pool by leaping from brain to brain via a process which, in the broad sense, can be called imitation.

Additional examples and other related information can be found in the essays listed under memes.

There's one very important thing about memes I forgot to mention. Memes, like genes, are selfish—they exist and propagate not for our benefit, but for their own. Here's how Dawkins put it.

What we have not previously considered is that a cultural trait may have evolved in the way that it has, simply because it is advantageous to itself.

The fact that memes are selfish may be just a consequence of the fact that memes are replicators, but I thought I'd mention it anyway, since it's very much a part of how I think about them.