An anti-language is a language developed and spoken by a subgroup within a major group. The purpose behind the development of an anti-language is varied. A sub-group may develop the language as a means of forming a bond among the members, such as in a cult or secret society. Another purpose may be to prevent the members of the outer society from understanding the meaning of the words spoken by the subgroup, such as is the case with gang members. The purpose may simply be as a means of rebelling against the dictates of a repressive outer society.
Anti-language may be used by members of a secret cult as a means of communicating with each other. Some of them may even develop a language that is understood by only members of the cult. This form of anti-language is used by such underground members of an anti-society as a means of keeping their activities secret.
The words spoken by the subgroup and used to form the anti-language are often corrupted versions of the words spoken by the major group. This may involve reassigning letters in words, putting different inflections, or using a different intonation to speak a version of the language. It may also mean ascribing new meanings to regular words or completely creating a new language from scratch.
An example of how an anti-language may be applied can be seen in the language used by thugs and street gang members. They may use different words to refer to something completely alien to the word. For instance, they may refer to a gun as a banana or any other word of their choice. To any other person listening, it would sound like the gang member was merely referring to a banana. Other members of the gang would immediately grasp that the person was talking about a gun.
Another example of the use of an anti-language is the development of a corrupted version of a regular language. The development of Pidgin English in some African countries where English is the official language is a corruption of the language. This form of anti-language contains elements of the English language, but with other additions and improvisations. Any English-speaking person listening to a Pidgin version will be hard-pressed to understand what someone speaking the language is trying to say. The person may catch glimpses of familiar words now and then, but it would be hard to totally make sense of the language.