An abridged series is an animation--typically a movie, tv show, or video game-- that is edited to be a shorter and fandubbed, usually for reasons of comedic parody. They are then usually posted on video websites, such as Youtube. The first and perhaps most popular example is the Yugioh: The Abridged Series which was created by LittleKurioh. Abridged series are sometimes created from collaborations, such as TeamFourStars which is doing an abridged series of DragonBallZ.
"Yugioh The Abridged Series is hillarious. It has terrific voice acting, writing, and editing."
"Adamwestlapdog made a funny abridged series on Zelda."
"NeighborhoodClucky's abridged movies awesome."
A youtube series parodying original TV series (usually anime) by taking clips from the show and dubbing them to make fun of the characters, plot, and over all the entire show.
"Dude! Avatar: The Abridged Series is so hilarious!"
"Yeah! I love how they made Zuko whiny, Jet paranoid, and Haru gay!"