Could someone please explain LGBTQIAC?

What's to explain?

Or more specifically, what is tripping you up?

[edit[

Speed stepped up and spelled it out. It puts pretty much all the categories in the acronym so nobody is left out including us straight folks, unless the strictly nonbinary folks get in a snit and insist on being included as their own letter, so then it would be LGBTQNIAC, which sounds like an experimental computer from the 1950s.

As to "what exactly does queer mean," you're going to have to do some research and determine that for yourself in the larger context of the generally accepted definitions. That's a deeper question than is fully appropriate for this forum.

I'd say give Speed the star since he actually answered the question in the first place.