You're thinking of the Yan, I think... and as far as they go, there's a passing reference to them in Action Stations and another one in Star★Soldier, neither of which go into detail or even determine who or what they are (the S★S gloss kind-of-sort-of-maybe-implies that they're aliens, but then that counts as unofficial material). Whatever the case and whoever-whatever they are, they're also in the 2300s, when Earth was under the Great Pandemic quarantine and before the Confederation even existed, so I'm not sure that "Terran" would even apply in this case.
As far as naming schemes go, Kilrathi War in particular, my take has been to either start off with Terran-Kilrathi War and then go into Kilrathi War, or else start with Kilrathi War, but link to the main article (which is, thankfully, Terran-Kilrathi War). Galactic War seems kind of obscure and I've never heard of Kilrathi War*s* until now (the movie does say "Pilgrim Wars"... subject that could use work).
Black Lance is the simplest and most recognizable name, and I'm just glad it exists to use. Qualifying stuff like "Dragons" and "212" is just too obscure. The Prophecy guide (and ICIS) use "Border Worlds Conflict", and I think the former also uses "Black Lance Affair". Those should probably be the big names.
Finally, Confed. The
Pegasus Naval Base dossier from the
Confed Military Installation Index, 2653 edition (from the Wing Commander Confederation Handbook) uses "Confed" to represent the Confederation - the only use of the full word "Confederation", in fact, is in reference to the Confederation Senate Security Committee which authorized construction. Then, of course, there's the name of the source (which itself is a confidential document).
Arnold Blair's obituary also uses Confed, and in fact does not use the term "Confederation" at all.
The novels produce an interesting one - to Forstchen and Ohlander (especially Ohlander), the Navy is always "the Fleet". I don't think Forstchen uses "Navy" once in Fleet Action or Action Stations, and Ohlander goes even further, building up and mythologizing "the Fleet" as an entity, whether it's in little toasts or names like "fleeties" or arguments over whether a Space Forces colonel is qualified to command a Fleet vessel. The latter is the one that's interesting to me: are the Space Forces a distinct entity and "Navy" and "Fleet" synonymous, or are the capital-ship Fleet and space-fighter Space Forces both subordinate parts of the Terran Confederation Navy, along with (presumably) the Terran Confederation Marine Corps? (A couple pages after the argument between Blair and Eisen, Dekkar mentions how the Space Forces left him on Repleetah, and how "Tolwyn had decorated the Space Forces commander for cool thinking" (232) - that doesn't sound like just fighters).
Action Stations further complicates things by not mentioning the Space Forces at all - apparently fighters are under the operational control of the Fleet, and everyone has navy-style ranks. (The Space Forces do apparently exist at this point, given Major Blair's obituary, but things come full circle by the film where everyone has naval ranks, Navy (Fleet?) or Space Forces.