This is the original meaning given by Dawkins in The Selfish Gene. The word ‘meme’ is more than a repeated fact – first, it doesn’t have to be a fact, and second, it suggests that our culture is the result of evolution in an environment where memes are selected for reproductive fitness (‘virality’).

> That’s like claiming any knowledge is a meme.

No, beliefs—whether true and justified (hence, knowledge) or otherwise—are not memes. Behaviors—including ones by which beliefs (including knowledge) are transmitted—are memes. If memes are viewed as analogous to genes (which is the whole point of the concept), beliefs (again, including knowledge) are among the features analogous to aspects of phenotype.

Any knowledge capable of self-replication is a meme.