Omnibus
An omnibus is a large hardcover that collects many issues of a comic series in one volume, often several hundred to over a thousand pages.
Where the word comes from
From the Latin omnibus, "for all" — the same word that gave us the bus. In publishing it has long meant a single volume reprinting several books.
In depth
In comics an omnibus is an oversized hardcover collecting a long stretch of a series — typically the material of four to eight trade paperbacks, sometimes a creator's entire run. Marvel, DC, Image and Dark Horse all publish omnibus lines, and manga publishers issue their own omnibus or "3-in-1" editions that bind several Japanese volumes together.
What you get
An omnibus usually reprints the issues in order with extras: covers, variant art, sketches, scripts or essays. Because it collects so much, it is often the most complete edition of a run and the easiest way to read it straight through.
The trade-off
They are heavy, pricey up front and can go out of print and become hard to find. Most readers buy an omnibus for a series they already know they want in full.
Omnibus and compendium
Some publishers use other names for similar books: compendiums and complete collections, often in softcover, collecting dozens of issues at a lower price per page.
What it means today
Manga "omnibus" editions are different in scale from American ones: a 3-in-1 manga omnibus collects three standard volumes, not three hundred issues. Check the page count and the volumes collected.
