Dissemination is the scattering of information. If you've done something really embarrassing and don't want the whole school to know, let's hope no one who saw you is an expert in the rapid dissemination of humiliating facts.
Dissemination builds on the word, seminate, meaning "to plan seeds." When you add the prefix dis-, you add the idea of separation, so to disseminate means to spread seeds widely. These could be literal seeds, like the dissemination of Oak genes by the scattering of acorns, or metaphorical seeds of ideas, like the dissemination of radical ideas through blogs, zines, and list-servs.