What is the term for switching between a person's first language and second language?

The term that describes switching between a person's first language and their second language is code switching. This phenomenon occurs in bilingual individuals who alternate between languages during conversation, often depending on the context, topic, or the people they are communicating with. Code switching serves various communicative functions, such as emphasizing a point, expressing a concept that may be better captured in one language, or even signaling a change in social identity.

Understanding code switching is essential in the context of bilingual education and ESL (English as a Second Language) instruction, as it can reflect a learner's comfort level, language competence, and social dynamics. It highlights the fluid nature of language use among multilingual speakers and demonstrates how language functions not only as a means of communication but also as a marker of cultural identity.

While the other terms listed refer to different concepts—language attrition pertains to the loss of language skills due to lack of use, Spanglish is a blend of Spanish and English, and transfer refers to the influence of a first language on the learning of a second—the focus on code switching captures the dynamic interactions that bilingual or multilingual speakers experience in their language practices.