My friend Rick Webb tagged me in a Facebook post asking for some clarification on whether the words limbo and liminal are related, and if so, are they related to the point of being synonymous which would make a sentence like “In permanent, liminal, limbo.” kind of bad English.
Here’s my explanation of why it isn’t the worst English, but also kind of is bad English, but how that isn’t really Rick’s fault and we probably have 13th century scribes to blame.

Ok here we go! Limbo comes to us from latin, limbus, meaning “edge, border, hem, fringe,” HOWEVER! There is some debate as to whether the word limbus originated in Latin, because it isn’t a particularly old Latin word comparatively.
The idea of Limbo as being a waiting place on the border of Hell was actually sort of a mistake made by English speakers way back in the 13th century. Basically the Latin word limbo is the ablative singular of limbus, so it would be used in latin phrases like “in limbo patrum” and English readers would say, “Oh that must mean literally IN limbo” and made Limbo into kind of a noun/name, but it really wasn’t correct. Correct latin would be “limbus patrum” which literally means an edge or border (of Hell) reserved for pre-Christian saints.
The word came into fashion as generally “a place of confinement, oblivion or neglect” in the 1640s.
Also just as an aside, the limbo DANCE has nothing to do with the limbo described above, and is simply West Indian alteration of the word limber. Limber probably comes from the word limb (in its definition as a bodily extremity), which is actually of proto Germanic origin (see the root word *limu-), but it got mixed up with the latin word limb meaning “edge” and the b was added, since people didn’t really have spell check back then and English was already getting confusing.
So let’s move on to liminal. Liminal is one of my very favorite words in any language so this is very fun for me, fyi. Liminal is an adjective, not a noun so that already sets it apart from limbo, and it comes from the Latin limen, which rather than meaning “edge or border” means “threshold” and though the idea of an edge or border and the idea of a threshold seem really similar to each other, they really aren’t once you dig into it.
Liminal spaces like thresholds are in-between spaces, and their sole purpose is as a space where things pass through and don’t remain. Airports are liminal spaces. The side of the highway is a liminal space. City parks are liminal spaces. Grand Central Station is a liminal space. The breaking of dawn and the setting of the sun are both liminal spaces. I LOVE liminal spaces. They are full of magic and weird energy because so many people trod through them but no one ever stays unless something’s gone very wrong.

So you can see how this word is very different from limbo, which means stuck or halted and unable to pass through. So even though they look the same, they really aren’t as related as one might think, but it’s totally reasonable to assume that at one point in time they both sort of came from the same arm of whatever proto language the sound “lim” formed in.
As another aside, my Somervillian Chinese uncle Jimmy’s last name is Lim, which in Chinese literally means “woods or forest,” as does the maiden name, Dubois, of his wife, my aunt Meg. The forest is truly one of my favorite of all liminal spaces, since most people pass through a forest, though some people do live there if they can.
