1620s, "council or body of representatives," from French syndicat (15c.), from syndic "representative of a corporation" (see syndic) + -at (see -ate (1)). Meaning "combination of capitalists or companies to carry out some commercial undertaking" first occurs 1865. Publishing sense of "association of publishers for purchasing articles, etc., for simultaneous publication in a number of newspapers" is from 1889. As a synonym for "organized crime, the Mob" it is recorded from 1929.
word-forming element attached to verbs, making nouns of state, condition, or action, from French -ion or directly from Latin -ionem (nominative -io, genitive -ionis), common suffix forming abstract nouns from verbs.
<a href="https://www.etymonline.com/word/syndication">Etymology of syndication by etymonline</a>
Harper, D. (n.d.). Etymology of syndication. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/syndication