When a book is unabridged it's the whole thing, with nothing cut out. If you're seeking a definition for a very unusual word, you may need to look in an unabridged dictionary.
To "abridge" something is to shorten it, so an unabridged edition has not been shortened. I can see that the short version of Shakespeare's works is easier to carry around, but if you want to enjoy every line, read the unabridged version. Unabridged is almost always used to describe books, but you can use it for spoken tales as well. You might not be so excited to hear the unabridged account of your sister's day at the mall.
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