Turku is an extinct Arabic-lexifier pidgin, formerly spoken in Chad. The only available description is found in Muraz (1926) and it consists of a brief grammatical sketch, a vocabulary, and six dialogues. Tosco & Owens (1993) have analyzed in great detail the phonology and morphosyntax of Turku; their study also includes two short sections on the vocabulary and an appendix containing the non-Arabic words in Turku, in which etyma are suggested only for borrowings from European languages. The present paper is the first investigation of the African component of the vocabulary of Turku, which consists of lexical items, including ideophones, as well as semantic calques. For each of these categories, wherever possible, their source languages are identified. It is shown that the source languages include mostly Sara-Bagirmi languages and Sango, but also Fulfulde, Hausa or Kanuri. A distinction is made between lexical items taken directly from various African languages and those which may have entered Turku via Western Sudanic Arabic, given their occurrence in Chadian varieties (Decorse & Gaudefroy-Demombynes 1905, Deredinger 1912, Lethem 1920, Jullien de Pommerol 1999, Behnstedt & Woidich 2011, Heath 2013, McKone 2013). The analysis of semantic calques makes reference to potential areal features, beyond genetic affiliations. The findings are briefly discussed in relation to the external history of Turku, with a focus on the sociohistorical context of its formation and use.