In academic circles, a noun for someone who engages in post-structuralist, post-modern or post-colonial research. Also can be used as an adjective to describe anything relating to this research. Generally used somewhat pejoratively.
That new researcher is working on subalternality in Italian refugee policy. She's a total postie.
So are you going to the postie conference? I hear that they're giving presentations on Agamben and Derrida.
A "post" bachelor party. A bachelor party for the guy AFTER he gets married, usually involving bars, drinking, strip clubs, strippers, etc. The wife may or may not be informed of the event. Occurs when the groom has eloped with the bride or has got married far from his friends. When he returns, the postie is thrown in his honour.