Verb, short for Preventative Blocking. Typically used on social websites that allow people to be blocked from communicating with you, and you wish to block them before communication is initiated as they are so vile and disgusting that just a hello will ruin your day.
Sean: OMG, did you see HryHngTop on Grindr? He sent me a dick shot without even saying hello!!!!

Steve: OMG, now way! I P-blocked that bitch weeks ago.
by steve1965 April 28, 2010
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