Which linguistic influence, substrate or superstrate, primarily shapes the vocabulary of a pidgin language?

The superstrate influence is the primary factor shaping the vocabulary of a pidgin language. The superstrate language is the language of the dominant group in the contact situation, usually the language of colonizers, traders, or rulers. It provides the majority of the vocabulary, also known as the lexifier language. For example, in Tok Pisin, English serves as the superstrate language and contributes most of the words. While substrate languages, which are the languages of the less dominant groups, do influence the grammar and sometimes contribute a few words, the bulk of the vocabulary comes from the superstrate. Therefore, a pidgin's lexicon is mainly determined by the superstrate language due to the power dynamics and social context in which pidgins arise.