cocoa powder
/ˈkəʊkəʊ ˌpaʊdə/(also cacoa powder, cocao powder)
noun
1A powder produced by grinding cocoa solids (sometimes mixed with other ingredients) and used to make various chocolate products.
2A brown slow-burning variety of gunpowder, made using a lower proportion of sulphur and less fully carbonized charcoal than conventional black powder.
Origin
Mid 19th century. From cocoa + powder.