Neologism: Simple definition, a made up word.
The most famous utilization of this (that I know of) is in the Jabberwocky poem by Lewis Carrol.
Also, e.e cummings is a poet I adore, who uses several neologisms. My favorite poem is pity this busy monster, manunkind
This is mine.
Underpath: (Noun/Adjective) [un-dur-pah-thuh]
1. The state of being where a person has tricked the collective into believing that they are a normal functioning member of society, when in actuality they are an undercover psychopath. Not to be confused with a sociopath, the underpath is able to blend in because their outbreaks are infrequent and unpredictable. For example, they can blame an outburst on a “bad day.” Most commonly, only two persons can identify an underpath, the underpath themselves, and the person who tries to convince the collective that this person is crazy, generally met with little success.
• Unfortunately the subversive nature an underpath makes it hard for everyone else to see that this person is mental.
• My dear friend Lizzie is an admitted underpath. I was shocked when she turned to me, smiling as always, and slit my throat. It is now Lizzie who lives my life. I am but a ghost.