A malamanteau is a neologism for a portmanteau created by incorrectly combining a malapropism with a neologism. It is itself a portmanteau of malaprop and portmanteau. Interestingly, malaprop is itself a 18th century malamanteau, combining the French phrase malaria de propane; that is, the funny feeling one gets when one breathes propane. However, Sir Michael Faraday discovered that this effect was actually just caused by oxygen deprivation, making the original phrase a malaprop. When soy jism was added, it became a malapropism.