Fae is another word for fairy, its a word that originated in Latin meaning fate, kinder, and godlike (that oversee childrens births? idk I'm just writing what I read). A Solitary Fae (google definition) = Solitary fairies, who live on their own, are more likely to be harmful. Leprechauns and banshees are solitary fairies. A Solitary Fae (actual definition) = Solitary fey are fey that don't belong to any particular court, or they live in the lands of a court but aren't seen as Seelie or Unseelie. They must abide by the rules, restrictions and commands of the court who owns the lands they live in. Seelie = is described as the fae who would seek help from humans, warn those who have accidentally offended them, and return human kindness with favors of their own. Still, a fae belonging to this court may avenge insults become violent if provoked far enough, as they are still living beings. Unseelie = is often used to describe the malicious fairies, although Unseelie members usually just dislike humans and occasionally act upon that dislike. Members of the Unseelie court are often more ruthless and malicious than their Seelie brethren. Hope this helps <3