Wikipedia
Schizoglossia is a linguistic term used to refer linguistic insecurity or language complex about one's mother language. It is common in societies where there are two language varieties and one is seen as incorrect and the other as proper. For example: Standard French versus Haitian French (often seen as a " creole") or Standard American English versus AfroAmerican English. In these cases, one variety is seen as "bad" and its speaker might want to correct some uses that are representative of it for some of the prestigious one. Those negative attitudes usually make the speakers be ashamed of the language that doesn't have prestige, either openly or indirectly (by using linguistic characteristics, such as pronunciation, of the other language).
The term was coined by Einar Haugen in 1962.