To be standing on the corner or in front of a building; usually involves protecting the block or territory;more commonly posted up selling drugs
"Yo homie we'll catch you lackin' later we stay posted on the block cuh."
When a friend on a social networking site leaves a comment on your status update that blocks all other friends from leaving further comments.
My aunt totally post-blocked me on fb when she wrote that god had the only real answer I was seeking. Nobody's going to comment on that one now!
when you post something and someone immediately posts something else, usually in an attempt to cover your post and/or drown it but can be accidental.
"dude, i posted a photo of my dog and it got post blocked by a meme."
"they are so annoying, they better not post block me again."
Similar to writers block only in the context of social networking sites. Unable to come up with post worthy content.
After logging into facebook and staring at the screen unable to post, I realized I was suffering from post block syndrome.