Wei’s Neologisms #3

Dysangelism

From Ancient Greek δυσ- (dus-, “hard, difficult, bad”) + ἀγγέλλειν (angéllein, “to announce”).

n. (dɪˈsændʒɪˌlɪzəm)

1. Sharing news of something that results in driving people away from joining or otherwise accepting it.

Antonyms: evangelism

UPDATE: Actually, it turns out that others have already come up with this term.