Myrmecophagous

Meaning: ant eating

Usefulness: 3 (Unless you work in a zoo, the only practical application I've come up with is to describe the suggestive Antz Pantz ad of the 1980s. Although as an insult "How myrmecophagous of you" could mean just about anything.)

Logofascination: 1 (Sir Thomas would approve of its construction: myrmeco-, meaning ant, and -phagous, eating, are both from Greek via Latin. I liked it so much that I resisted the more topical hippophagous.)

Cheesecake

Meaning: I'm sure we all know what it means, but if you want a titbit to start with, placenta originally meant cheesecake. No, really: placenta is from the Latin and Greek for 'flat cake', and Wikipedia mentions Cato's recipe for placenta, a cheesecake made for religious purposes.  I'm considering abandoning Artotyrism for a religion where cheesecake is central.

Usefulness: 2 (Cheesecake is often useful, and home-made baked cheesecake is always useful.)

Logofascination: 1 (Logofascination is expressed in many ways, including: the etymology of placenta; discovering that the word cheesecake has been around for 570-odd years; exploring the history of cheesecake all the way back to the Greeks; learning that there's a cheese called quark which allows you to have quark desserts such as quarkstrudel; and, finally, that the term beefcake originated from the slang use of cheesecake, somewhere in the 1940s or 50s: hoorah for the female gaze!)

Myrmidon

Meaning: a flunky, although wiktionary takes it one further: someone "who executes orders of a superior without protest or pity".

Usefulness: 1 (Let's face it, you either are one, or you'd like some)

Logofascination: 2