The definition of propaganda is:
It is chiefly a derogatory term.
Information, especially of a biased or misleading nature, used to promote or publicize a particular political cause or point of view.
The dissemination of propaganda as a political strategy: the party's leaders believed that a long period of education and propaganda would be necessary.
ORIGIN
Italian, from modern Latin congregatio de propaganda fide ‘congregation for propagation of the faith’
American English Thesaurus:
the prophetic novel is about a government that controls the masses by spreading propaganda: information, promotion, advertising, publicity, spin; disinformation, counter-information; historical agitprop; informal info, hype, plugging; puff piece; the big lie.
British English Thesaurus:
regulations restricting political propaganda were relaxed: information, promotion, advertising, advertisement, publicity, advocacy; spin, newspeak, agitprop, disinformation, counter-information, brainwashing, indoctrination, the big lie; informal info, hype, plugging.