I trolled the internet for definitions and the one I like the best came from the ubiquitous Wikipedia:
In architecture, a plinth is the base or platform upon which a column, pedestal, statue, monument or structure rests.[1] Gottfried Semper's The Four Elements of Architecture (1851) posited that the plinth, the hearth, the roof, and the wall make up all of architectural theory. According to Semper, the plinth exists to negotiate between a structure and the ground. Semper's theory has been very influential in the subsequent development of architecture.[2]
I especially like the line, "exists to negotiate between a structure and the ground."
Why I dreamed this word, I have no idea. Maybe I should ask a Jungian. Here are a couple of more gratuitous plinth pics:
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Here is a different kind of plinth...evidently it is also a kind of sophisticated, articulating medical chair:
And here's a short video about an art project involving a famous plinth and a bunch of English folk:
Has anybody else ever had a dream about a word? Next, I just need to start working it into as many conversations as possible.