COCACAO

The earliest English attestation of the word cocoa in its current sense (describing the seeds used to make chocolate, or the powder produced from them) is from French explorer François Froger's 1698 account of his voyages in Africa and the Americas. Before that, however, the word was in use for several decades to refer to the cacao tree, which produces those seeds. The noun actually comes from cacao, but it was corrupted by influence from the word coco, meaning "coconut palm". This mistake was then adopted by the time Samuel Johnson's highly influential Dictionary of the English Language came out in 1755., and then it could never be undone. Cacao comes from the Nahuatl word cacahuatl and is reconstructed to Proto-Nahuan kakawatl, with the same definition. Coco, if you were interested, comes from a Spanish and Portuguese word meaning "grinning face", because apparently that's what they thought coconuts looked like.