Brebes Sundanese Language (BSL) is a Sundanese language that exists in Brebes District, in the Center of Java. Brebes Sundanese Language growing in territorial of Java – Sunda’s borders and far from the center of the Sundanese language. This paper discusses the shapes and traits of the Sundanese language used in Brebes District in the realm of social intercourse. This research uses a sociolinguistic theoretical approach and an ethnographic methodology of communication approach. An observation method is used for data collection. The results of the analysis show that Brebes Sundanese Language in the realm of social intercourse is a mixture of Sundanese language and Javanese language. The use of Brebes Sundanese language in the realm of social intercourse indicates the absorption of Javanese language ( JL) in BSL, which lasts a long time and is not realized so it becomes a shared code. The use of BSL in the realm of social intercourse shows a uniqueness at the phonological level, and in morphology, lexicon, and syntax. BSL as an identity of this territory shows that the people of Sunda Brebes are natural and open.
Keywords: Brebes Sundanese Language, identity, lexicon, realm of social intercourse