From USAtoday.com….
You’ve likely started to hear the term “nonbinary” more frequently. On Wednesday, Demi Lovato announced they were nonbinary and changed their pronouns to they/them.
“Nonbinary” refers to someone who does not identify only as a man or a woman, i.e. the traditional gender binary, according to the Human Rights Campaign. They could identify as both a man and a woman, in between the two genders or not a part of any gender category at all. GLAAD offers a similar definition.
Someone who is nonbinary may also be transgender – Elliot Page, for example, identifies as both – but that is not always the case. GLAAD recommends only calling someone nonbinary if they claim that identity themselves.
It has become increasingly common for some people who identify as nonbinary use a singular “they/them” pronoun.