Poking around on the trail of “flink,” I came upon what may be the explanation for its apparently sudden appearance sometime around 2002. In an article in one of the behind-the-scenes parts of Wikipedia, a user suggests that “flink” might be a fanciful invention based on the “cow” of that “cowardly” in the OED definition, and that, furthermore, “flink” might actually be a “mountweazel” that has, so to speak, escaped into the wild.

A “mountweazel,” as I explained a few months ago, is a spurious entry deliberately included in a dictionary or encyclopedia in order to trap plagiarists. (The name comes from a fictitious entry for Lillian Virginia Mountweazel, supposedly a famous photographer of rural mailboxes, included in the 1975 edition of The Columbia Encyclopedia.) It seems entirely possible that “flink” was invented as such a mountweazel for a text, perhaps an electronic dictionary, which was then widely plagiarized on the internet, giving the imaginary “flink” a life of its own. Of course, if “flink” is still popping up on the internet in a few years, it’ll be time to begin considering it a “real” word fit for “real” dictionaries.

http://www.word-detective.com/2011/03/flink/