Irredentist

Meaning: with a lower-case i, someone who advocates seizing territory back* from another nation or state. With a capital, a member of a 19th century Italian political party which advocated the annexation of Italian-speaking districts from surrounding nations.

Usefulness: 2 (Slightly abstruse, but you'll get points from the politically inclined. Could be useful if you were interviewing Diego Marani, who likes to discuss the attempts of nation-states to co-opt language as identity and/or delineator of borders, and the way that the EU is - possibly - undoing that. Podcast here, or interview here. He's also attempted a universal language, albeit a Euro-centric one.)

Logofascination: 2 (From the Italian for 'unredeemed', as in 'unredeemed Italy'.)

In the wild: A Washington Post blogpost on the issues with a study that supposedly mapped 'racial tolerance'.

Myki

Meaning: Old Norse for cow dung. No, really. See also here.

Usefulness: 1. (Google tells me that there was a bit of press about this when the system first came out, but no-one told me.)

Logofascination: 1 (Etymologically related to muck and midden.  Mainly of interest to those of us residing in Melbourne; myki is our public transport ticketing system. Its problems are so notorious that there's a hashtag: #mykifail. I suppose it provides the rest of you with a usefully obscure word for cow dung; "This report is sheer myki!")

In the wild: Of all places, I found it in a post on Lancashire dialect. I'm trying to figure out where loomster comes from.

Degrees: 3

Connections: myki - muck - manurers (It's been a while since we had a word this far removed; I think this is because Sir Thomas used Scottish vernacular rather than English - muck and midden - and the influences are different.)

Which is used in: Logopandecteision. To over-simplify, Sir Thomas is arguing that you can verify how ancient his heritage is by considering that of his tenants:

both historie and the most authentick tradition we have, avoucheth the first labourers and manurers of the land to have come along with my ancestors Beltistos, Nomostor, and Lutork, and for their good service done, especially to the last of those three, received leases thereupon in the quality of yeomans, who were so well pleased with what they got that after they had most contentedly spent the best of their age, when decrepit years did summon them to pay their last due to nature, they bequeathed unto their children the hereditarie obedience they did owe their master, to whom they left their blessing and best wishes 

Manure originally just meant cultivate, but of course manuring is one of the chief activities of cultivation, particularly before modern fertilizers. 

Accidence

Meaning: Inflectional morphology. (Helpful, eh?) The parts of grammar that are concerned with the way words change to indicate different things - conjugation, declension and so on.

Usefulness: 2 (At first I thought this might mean I wouldn't have to think about whether a word was being conjugated or declined, but after writing that definition I think I'm better off sticking with my basic verbs-are-conjugated theory.)

Logofascination: 1 (It's accidents, but this specialised term has developed from the sense of an accident as something incidental, not of the essence. So number and gender are incidental - accidental - to some words, rather than essential, and are therefore expressed through inflection. The word cars indicates that there is more than one car, but the car-ness of the cars involved is not altered by the -s; the plural is an accident.*)

In the wild: Mentioned in Asterix, and explained rather better in the post translating the Latin joke in the same comic: it's funny, if you find grammar amusing.  There's a post for every Asterix book here - I'm going to be scouting second hand bookshops for a while, as it's brought on a terrible nostalgia for them.

Volery

Meaning: A flock or flight of birds, or a large aviary - Cotgrave:

A great cage, or coope wherein birds have roome ynough to flutter.

Usefulness: 2 (Mainly to trick people; I was quite excited when I saw this word, because I liked the idea of something full of voles.)

Logofascination: 2 (This might be coloured by my disappointment on discovering that voleries are not, in fact, full of voles, but it is an example of the quirks of word formation. From the French word voliere of the same meaning, in turn from voler, to fly, and etymologically unrelated to the vole.)

In the wild: Gets mentioned occasionally as an exotic collective noun.

Proquiritations

Meaning: the Dictionary of Scots Language has "to cry out in public, publish, proclaim", but for reasons outlined below, I think Sir Thomas meant "to publicly protest on behalf of another".

Usefulness: 1 (Can be used seriously: "The proquiritations of the Occupy movement seem to have made little difference". Or not: "It's always good to see Australia beat England, particularly when English proquiritations regarding umpiring provide an excuse to call them whingers.")

Logofascination: 1 (Quiritations are cries for help, complaints or protests, and I think Sir Thomas has added the 'pro' to emphasise that these protests are on behalf of someone else. The Proquiritations are supposedly written by 32 other people arguing that Sir Thomas should be excused from paying his debts, of which there were, apparently, many.)

Naufragous

Meaning: Causing shipwreck.

Usefulness: 1 (Besides reefs and certain parts of the Victorian coastline, this word is terribly useful in a figurative sense. Since almost anything can be wrecked - prospects, plans, hearts - anything that wrecks can be metaphorically naufragous.)

Logofascination: 1 (One of those words that makes me think there really is a word for everything. Related to navicular, of course, but also to the frangere family - so something naufragous is something that renders ships frangible.)

Epassyterotically

Meaning: according to Sir Thomas, "one after another". Since he invented it, he should know.

Usefulness: 1 (Sir Thomas uses it of a killing men and of paying bills, so it's rather versatile.  Gets extra points for potential confusion: "I've booked meetings epassyterotically today." "I beg your pardon?" "You know; one after the other." )

Logofascination: 1 (I think I need to learn Greek; the OED tells me this is from ἐπασσύτερον, epassyteron - 'one upon another'. I'm fairly sure the ep- is related to epi- in episode and epicentre, but after that I get stuck. It doesn't seem to be related to erotically, though I'm sure Sir Thomas appreciated the semi-homophone. I recommend reading the etymonline erotica entry anyway, as an exercise in appreciating the effect of being surprised by poetry. Yet another sola word, for which Sir Thomas is the only citation in the OED.)

Appetenda

Meaning: to be sought

Usefulness: 2 (The to be formation makes these words slightly difficult to use.  "It's Friday night, so cocktails are appetenda!" However, the sermon mentioned on Monday is now complete: that which is to be believed, done, fled from, feared, and sought. I think this could also be a useful way to plan your life - what are my credenda, facienda, fugienda, timenda and appetenda? There's a self-book in that, I'm sure.)

Logofascination: 1 (from petĕre, to seek, appetenda is word-cousins with appetite, centripetal, compete, repeat, petition, petulant, ... and so on.)

Thropple

Meaning: a Scottish dialect word for the throat, more specifically the windpipe or larynx.

Usefulness: 3 (Perhaps if someone asks you to do a bad Scottish accent, or if, like me, you need a reason to mention that one of the last speakers of a Cromarty dialect has died recently.)

Logofascination: 3 (possibly not that fascinating, but it is used twice in an English translation of a French work. And it's quite old.)

Temulentious

Meaning: tending to be intoxicated, drunk

Usefulness: 1 (an appropriate word for a Saturday: "The city was full of temulentious footy fans." "Friday was temulentious, so Saturday was rather slow.")

Logofascination: 1 (temulent is the base, and also gives us temulence, temulency, temulentive, etc.)

Ergastularies

Meaning: workhouses, although I like to think that Sir Thomas uses it more as we would 'factory'; it's related to the Latin for a house for slaves or other workers on an estate (ergastula).

Usefulness: 1 (This is what I'm calling my office from now on, and I quite like my job. Also handy to refer to those vast soul-destroying office 'parks')

Logofascination: 1 (all 0 degree words get 1; here Sir Thomas has Anglicised a Latin term - ergastulary, rather than the ergastulum/a/i. This word is referred to so little that it's not even in the OED, something I will be suggesting they rectify.)

Pandect

Meaning: a book of everything! Used by the Romans to refer to books of the law, this word's Greek origins mean all-receiving (an inn-keeper was a pandocheus). It was apparently the title of a few works of 'universal knowledge', or as we might call them, encyclopedias.

Usefulness: 1 ("I refer you to the great pandect, Wikipedia..." "My satchel is weighed down by the latest tax pandects." "The company OHS pandect has been revised as a direct result of your behaviour at last week's dinner.")

Logofascination: 1 (Romans and Greeks and, yes, Sir Thomas)