Among the things in the Old Tongue vocabulary within the Companion, were the translations of the Forsaken names and the names of the Trolloc bands. Curiously, Ba'alzamon is listed in the Old Tongue vocabulary, when the books had always contended it was in the Trolloc language. The Companion makes no mention of a separate language in the Trolloc entry. Anyway, I had assumed the names of the Trollocs were just names, and in their tongue if any, but they are actual Old Tongue words. The meanings are as follows, with the known symbols of the bands in brackets. Those are not in the Companion to my knowledge, but were gleaned from tGH & KoD.

Ahf’frait: Strong wind {silver whirlwind}
Al’ghol: The soulless {hooked axe}
Bhan’sheen: Bringers of annihilation {dagger-pierced skull}
Dhai’mon: Scythes of war {iron fist}
Dha’vol: Sires of agony {horned skull} Elsewhere, it is noted that -vol specifies a brutal sire, such as a rapist.
Dhjin’nen: Those who cause terror {skull cloven by scythe-curved sword}
Ghar’ghael: Brutes of venom {piled human skulls}
Ghob’hlin: Harvesters of souls {symbol unknown}
Gho’hlem: Takers of souls {symbol unknown}
Ghraem’lan: Prized of the mighty {forked lightning}
Kno’mon: Scythes of destruction {red, bloodstained fist}
Ko’bal: Circle of one, i.e. brotherhood {blood-red trident}

The Forsaken names {with my interpretations of what an equivalent name would be in some cases where the literal translation is an awkward phrase in brackets}:
Aginor: Slicer of the living {Vivisectionist}
Asmodean: Musician
Balthamel: Essence of youth {given his nature, I would guess an analogous idiom would be something like “Wild Child” or “Frat Boy” with implications of self-indulgent immaturity}
Be’lal: Desire to have; the Envious
Demandred: One who twists the blade {Sadist or Tormentor}
Graendal: Vessel of pleasure {Slut, or maybe Hedonist}
Ishamael: Betrayer of hope
Lanfear: Daughter of night
Mesaana: Teacher of lessons
Moghedian: type of spider
Rhavin: Promise of freedom {I would presume there is an implication of license more than freedom here}
Sammael: Destroyer of hope
Semirhage: Promise of pain
Moridin: Death
Cyndane: Last chance
M’hael: Supreme leader
Hessalam: Without forgiveness {Unforgiven}

I don't think I'd ever even seen a guess as to what Balthamel or Demandred were. I know a lot of people guessed at things close to the actual meanings of Semirhage, Mesaana, Graendal or Aginor, but they probably missed big time with Rhavin.