propagation vs dissemination

propagation and dissemination both are nouns.

Word	Noun	Adjective	Verb	Adverb
propagation	Yes	No	No	No
dissemination	Yes	No	No	No

As nouns, dissemination is a hypernym of propagation; that is, dissemination is a word with a broader meaning than propagation:

propagation: the spreading of something (a belief or practice) into new regions
dissemination: the opening of a subject to widespread discussion and debate

Other hypernyms of propagation include airing, public exposure, spreading.

propagation (noun)	dissemination (noun)
the act of producing offspring or multiplying by such production	the act of dispersing or diffusing something
the spreading of something (a belief or practice) into new regions	the property of being diffused or dispersed
the movement of a wave through a medium	the opening of a subject to widespread discussion and debate