Русско-англо-русский юридический словарь

The common law origins of defamation lie in the torts of "slander" (harmful statement in a transient form, especially speech) and "libel", each of which gives a common law right of action. Defamation is the general term used internationally, and is used in this article where it is not necessary to distinguish between "slander" and "libel". Libel and slander both require publication. The fundamental distinction between libel and slander lies solely in the form in which the defamatory matter is published. If the offending material is published in some fleeting form, as by spoken words or sounds, sign language, gestures or the like, then it is slander. (Wikipedia)

Libel is defined as defamation by written or printed words, pictures, or in any form other than by spoken words or gestures. (Wikipedia)