A neologism for a portmanteau created by incorrectly combining a malapropism with a neologism. It is itself a neologism, a malapropism and a portmanteau (of malapropism and portmanteau).
Somebody describes his misunderstanding of what someone was saying by stating, "I misconscrewed it up."
Someone explains his inability to talk while being upset by saying he was "flustrated."
A meaningful malamanteau is "ambiviolent," as in: "Beatrix Kiddo in Kill Bill was ambiviolent. She didn't know who to kill first."
George W. Bush's inadvertent malamanteau "misunderestimated" has entered common usage.
Someone describes being misinformed as "being miscommunicado", a mixture of miscommunicate and incommunicado.
The discussion in the wikipedia page for 'Malamanteau' is a "Wikibroidery" (Wikibroglio)