Pidgin

A pidgin, or pidgin language, is a grammatically simplified form of contact language that develops between two or more groups of people that do not have a language in common, and its vocabulary and grammar are typically limited and often drawn from several languages. The cited article says it is most commonly employed in situations such as trade, that it is not the native language of any single speech community but can be learned as a second language, and that pidgins have historically been considered unsophisticated, simplified versions of their lexifiers and usually have low prestige. It also notes that each pidgin has its own norms of usage which must be learned for proficiency. Varieties the atlas records as pidgins are grouped under this entry.