Meaning: very, very nasty; usually used in association with crime: "flagitious crime".
Usefulness: 1 (Sadly.)
Logofascination: 1 (Fascinating, but confusing; although at first glance I thought it would be a cousin to flagrant, it seems to be more closely related to flagellation. The OED links the flag- back to the same root as flagrant, but etymonline has different Proto-Indo European roots for them. The OED entry hasn't been updated since 1896, so I'm going with etymonline, meaning that etymologically, this refers to crimes resulting in scourging.)
In the wild: No; I'm rather suprised newspapers and politicians haven't resurrected it.
Which is used in: G&P, Book the Second (Pantagruel), VI: How Pantagruel met with a Limousin, who too affectedly did counterfeit the French language. We've discussed the Limousin's outrageous language previously - Rabelais has flagitiose as one of the many long, Latinate words used by the Limousin to defend his speech:
My worshipful lord, my genie is not apt nate to that which this flagitious nebulon* saith, to excoriate the cut(ic)ule of our vernacular Gallic, but vice-versally I gnave opere, and by veles and rames enite to locupletate** it with the Latinicome redundance.The text here suggests that Rabelais looks down upon such 'Latinicome redundance', but throughout G&P he demonstrates his own love for language, and coined a number of words - admittedly, some in satire. Did Sir Thomas identify with this Limousin, or did he see his own neologisms as of a different class?
*coming soon to this blog