Avoidance speech is a group of sociolinguistic phenomena in which a special restricted speech style must be used in the presence of or in reference to certain relatives. Avoidance speech is found in many Australian Aboriginal languages and Austronesian languages as well as some North American languages, Highland East Cushitic languages and Southern Bantu languages. Chinese naming taboo prohibits speaking and writing syllables or characters that appear in the names of esteemed people, such as emperors, parents, and ancestors. Avoidance speech styles tend to have the same phonology and grammar as the standard language they are a part of. The lexicon, however, tends to be smaller than in normal speech since the styles are only used for limited communication. Australia Mother-in-law languages Avoidance speech in Australian Aboriginal languages is closely tied to elaborate tribal kinship systems in which certain relatives are considered taboo. Avoidance relations differ from tribe to tribe in terms of strictness and to whom they apply. Typically, there is an avoidance relationship between a man and his mother-in-law, usually between a woman and her father-in-law, and sometimes between any person and their same-sex parent-in-law. For some tribes, avoidance relationships are extended to other family members, such as the mother-in-law's brother in Warlpiri or cross-cousins in Dyirbal. All relations are classificatory – more people may fall into the "mother-in-law" category than just a man's wife's mother. Avoidance speech styles used with taboo relatives are often called mother-in-law languages, although they are not actually separate languages but separate lexical sets with the same grammar and phonology. Typically, the taboo lexical set has a one-to-many correspondence with the everyday set. For example, in Dyirbal the avoidance style has one word, jijan, for all lizards, while the everyday style differentiates many varieties. In Guugu Yimidhirr the avoidance speech verb bali-l "travel" covers several everyday verbs meaning "go", "walk", "crawl", "paddle", "float, sail, drift", and "limp along". Corresponding avoidance and everyday words are generally not linguistically related. Avoidance forms tend to be longer than everyday forms. In some areas, the avoidance style is used by both members of the avoidance relationship; in others the senior member may talk to the junior in everyday style. Behavior associated with avoidance speech is a continuum and varies between tribes. For the Dyirbal people, a man and his mother-in-law may not make eye contact, face one another or directly talk to each other. Rather, they must