Definition of "transmedia"
Of or relating to more than one form of media.
Quotations
The Star Wars novels, comics, video games, television series, and radio shows created between 1977 and 2012 all constitute an original Expanded Universe (EU) of in-universe history and lore set within the same transmedia franchise.
2019, Monica Louzon, “Mara Jade, Frontier Woman”, in Melanie A. Marotta, editor, Women's Space, Jefferson, North Carolina: McFarland & Company, page 29