To refuse to take no for an answer when requesting a loan/handout from others (i.e., asking them to "open their purses").
I have totallygiven up on "loaning" money to the local moochers ('cuz they seldom pay me back --- duhhh), but some of them are surely purseistent in continuing to ask me, anyway.
A trend which remains relevant for far too long, to the point of annoying those actual cool people who years ago, were aware of, and/or adopted the trend and now have abandoned it and consider it a lame ass relic. Examples include: nerdy glasses, Lady Gaga, hipster culture.
A rare medical condition, first posited by Nelson on the BBC TV puppet comedy Mongrels, which causes patients given twenty four hour care to live for years and years and years, despite having multiple diseases, ailments and genetic disorders that would otherwise fatal.
"Still, not being horrible or nothing but he probably won't last that long."
"That's the truly wonderful thing actually. He's got a condition called "Persistent Forsyth Syndrome". Given twenty-four hour care, he'll live for years and years and years. And years. And years. And years. Which is obviously *yawn* really great news."