At a sensory boundary or threshold, a transitional state between one stage and the next as in the boundary between life and death.

So, of course sub-liminal means below the state of that threshold of consciousness when you become aware of something.

The reason why this glossary became called “Liminal Lexicon” is not just because it sounded good, but because that sensation that you have something on “the tip of your tongue” represents a liminal state. You’re aware that you know the word, but just cannot access it. I wanted to write about words that are either strange, ones that have not yet entered our dictionaries, words that should exist but do not..but wanted to extend that to also writing about fantasy creatures, fictitious liminal realms and the like.

I’ve heard the term “liminal space.” These are either spaces that are in a stage of transition, or that pass you through a transition. So both an abandoned building and a waiting room would be a liminal space.

If I had to use liminal in a sentence at this very moment, I would say “I am in that liminal phase between my younger self and old age.”