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It's not really a short form of a word but a changed word. Remove the p and replace it with an o.
Many forums will block the original word (with the o) and so, many posters will replace the o with a p.
In the usage that RejZoR posted above, it means that something is much better than something else.
By the way, there have been a few times I have disagreed with RejZoR and once or twice maybe when I have disagreed with Polonus ... though with both, it has been quite a while since that has occurred. Well, at least publicly it has been quite a while.
Perhaps it is that I have similar thoughts and ideas on subjects that they post. As you might have also observed, I do not start many posts. My time is limited and therefore, I am usually reading & answering or replying in posts/threads started by others.
And, there have been times when I have agreed with you, alan ... as well as times when you have corrected me on misinformation I gave. I haved publicly thanked you for that.
I hope this has answered your question. If not, please let me know.
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