Glosso’s word of the week: “Clairaudience”

I’m rereading one of my favorite old novels — from 1949 — and just came across a word I wasn’t aware of before. I had no trouble understanding its meaning when it appeared at the end of these two descriptive sentences:

“The first time Henrietta came to the house and sat herself with Mother in the drawing-room, my pungent interest, my complete certainty that they were talking about me, drove me to the closed door that I might hear their actual words. And it seemed that my certainty was a true clairaudience.”

As defined by Oxford Dictionaries, clairaudience means: “The supposed faculty of perceiving, as if by hearing, what is inaudible.”

I wonder why clairvoyance took off, but clairaudience didn’t?