Skoliosexual is a relatively new term that refers to people who are attracted to people who are transgender or nonbinary.
The skolio- in skoliosexual comes from a Greek root meaning “bent” or “curved,” seen in the word scoliosis.
The term was coined in 2010 by a DeviantArt user, Nelde, who made a comprehensive diagram of sexual attraction. Nelde noted using the Greek root as a gloss for the English queer.
Skoliosexuals are attracted to people who identify as nonbinary (i.e., a gender identity that doesn’t fit into traditional male/female and heterosexual/homosexual divisions). Attraction between two people who are nonbinary, for instance, may be described as skoliosexual.
Many in the queer community prefer the term ceterosexual, with cetero- (think et cetera) based on the Latin for “other,” given how “bent” and “curved” can imply something is wrong with nonbinary people.