Was done on this subject but I have to answer your comment. Did you even read the definition I posted on Defamation? Here I'll give to you again. Look closely at the bolded portion.
Defamation—also called calumny, vilification, traducement, slander (for transitory statements), and libel (for written, broadcast, or otherwise published words)—is the communication of a statement that makes a claim, expressly stated or implied to be factual, that may give an individual, business, product, group, government, or nation a negative image. This can be also any disparaging statement made by one person about another, which is communicated or published. It is usually a requirement that this claim be false and that the publication is communicated to someone other than the person defamed (the claimant).[1]
Libel, Slander, and Defamation is same thing according to Defamation definition.