This research discusses the form of defence of the southern coastal community which is frequently considered strange by most of the Indonesian archipelago community. The analysis began with discussing the linguistic phenomena of the local community, identifying and corroborating the findings as initial capital to determine the analysis method. The findings can be useful for making corrections or structuring social and cultural policies towards indigenous/local wisdom and preserving cultural identity. The research was oriented to the speech lexicon of the Southern coastal communities of Central Java. This research used descriptive qualitative and contextual approaches. The analysis used to describe the speech component was dialect geography and collaborated with an anthropological-linguistic approach to find innovative forms and factors that maintained local identity. As the southern coastal chain of Central Java, bordering with West Java, the nuances of cultural acculturation as a form of cultural pluralism are very visible. Cultural acculturation results in the emergence of language enclaves. The language enclave is formed because the speech community has a speech code that is different from the mother tongue and the nearest language. Language enclaves formed on the southern coast of Central Java occur at the level of internal innovation. Internal innovations in the southern coast language enclave occur in the form of allophones and allomorphs that can be traced based on the articulation process. Social heritage as a form of language preservation in the language enclave of the southern coast of Central Java is formed by the characteristics of simplicity and social intelligence of the people.