Thought I'd make a thread to discuss what each demon's race means, and in the case of untranslated races (Jaki, Kishin, etc.), a suitable translation.
Light - Law:
Herald/Seraph - High ranking monotheistic angels.
Megami - "Goddess". Benevolent, powerful female deities
Avian - Holy birds, associated with gods and known for benevolent deeds.
Tree - Benevolent deities who are/are associated with flora.
Neutral - Law
Divine - Abrahamic angels.
Flight - Supernatural bird creatures, not as powerful as deities.
Yoma - "Demon", more specifically refers to demons associated with the dead, like Shiwanna that are formed from the dead, or Valkyrie who claims them.
Nymph - Not sure. I think they're female spirits that are able to easily charm their targets.
Dark - Law
Vile - Malevolent gods, or gods reviled by worshipers of their pantheon.
Raptor - Melevolent bird-like entities.
Wood - Dangerous/Malevolent supernatural creatures associated with flora.
Light - Neutral
Deity - Benevolent gods of polytheistic religions.
Avatar - Animal-like gods.
Holy - Animals associated with gods, serving as their steeds or likewise.
Genma - Generally means a being wielding great supernatural power, in this case benevolent as well. More info: http://en.wikipedia.org/wiki/Genma
Mitama - Aspects of the human soul, according to Shinto belief.
Prime - Embodiment of the classical elements.
Enigma - Not sure.
Neutral - Neutral
Fairy - Supernatural European beings, generally good-natured but mischievous.
Beast - Important animals in various religions.
Jirae - "Earth Spirit". Supernatural creatures associated with the earth or nature.
Snake - Serpentine beings in lore.
Dark - Neutral
Reaper - Gods of death.
Wilder- Evil beast-like entities, usually of low intelligence.
Jaki - "Evil spirit". Malevolent supernatural beings in general with few other traits.
Vermin - Reviled, animal-like demons.
Fiend - Extremely powerful beings associated with death, some being former humans.
Zealot - Feared gods or demigods.
Light - Chaos
Fury - Gods associated with violence and/or destruction, though generally benevolent.
Lady - Female deities associated with war or destruction.
Dragon - Benevolent serpentine beings, usually associated with nature
Kishin - "Demon God", benevolent beings associated with war, strength or protection from evil.
Geist - "Mind" or "Spirit". Appears to mean deities with no true corporeal form. More info: http://en.wikipedia.org/wiki/Geist
Neutral - Chaos
Fallen - Demons of the Goatia, said to be angles that had fallen due to their attempted rebellion.
Brute - Monsters known for their strength.
Femme - Generally evil or neutral female beings.
Night - Demons associated with the night, or illusion.
Dark - Chaos
Tyrant - Powerful, malevolent demons, often demanding sacrifices from their followers.
Drake - Malevolent dragon-like or serpentine beings.
Spirit - Evil ghosts or beings able to possess humans.
Foul - Indeterminate, incomplete monsters, unable to do anything great.
Haunt - Evil beings born from the deaths of tormented humans.
Mother - Refers to Mem Aleph's position as a mother of many beings.
Empty - Refers to Mem Aleph after losing all reason, only wanting to kill the protagonist before dying herself.
Shinrei - "Godly Spirit". Used for an extremely powerful Abrahamic being.
Choujin - "Superhuman". Humans who have undergone some kind of transformation to gain power.
Light - Being known for its powerful light.
Devil - Extremely powerful being of chaos, an archenemy to Law.
Hallel - "Praise", refers to fallen angels who have been redeemed.
Asura - Powerful beings who require the consumption of human flesh to sustain themselves.
Yaksa - Means nature spirit, similar to Asura, not sure why they are classified differently.
Onmyo - Refers to Onmyodo, a philosophy of Yin and Yang, referencing Hari-hara's design and concept.
Awake - Human who has fused with a demon. The title is possibly a reference to "Awakened Beings", in the manga Claymore.
Soil - Human/Demon hybrid powered by the Earth.
Judge - Human who has been transformed into an angel capable of subduing unlawful beings with their voice.
Pillar - Human/Angel who is intended to serve as a channel to YHVH, subduing all of humanity to do so.
So.. yeah. Discuss, etc. I'd really like Atlus to translate all demon races, not being able to understand them really has them lose a lot of meaning.