Gender neutral pronouns:
they / their “They forgot their ice cream”
ze (also spelt zie or sie) / hir “Ze ate hir chocolate cake”
yo – interesting article about this one here “Yo went to the store, we’re waiting for yo to get back”
There is a much longer list of gender neutral pronouns about halfway down this page.
nibling – gender neutral version of niece/nephew
sibling/kid/parent (you should know these ones!)
enbyfriend – gender neutral version of girlfriend / boyfriend
A gender neutral language wiki over at nonbinary.org.
Mx it up – a grassroots campaign for gender neutral titles in the UK