(Rant) The Horror of Indescribable

One thing that annoys me in Mythos horror, especially when it comes to rpgs,  is the overuse (or rather any use) of the word "indescribable".  To his credit Lovecraft used the term infrequently, because he had a vast store of sespequidillion words he drew on.  Its the writers with a scanty store of words that overuse the term, as shorthand for cosmic horror we can't understand.   And in RPGs, all too often it's used as a cheap crutch for unimaginative GMs. 

Which can backfire, as so:

"You gape at the indescribable terror of the elder god.  Then his writhing tentacles reach out, grab you and -"
"Hang on, what tentacles?"
"The elder gods tentacles, duh. Anyway, they grab you and-"
"But you said it was, quote, indescribable."
"...Yeah, so?
"Well, you just went and described it. You said it had tentacles!"
"It's an Elder God! Of course its indescribable!"
"Make up your mind. Either it's indescribable, or it's got tentacles. Can't have both."
"It's got to have tentacles to grab you!"
"That's not MY problem."

The moral being, in a medium that depends on verbal communication, always describe, don't tell.  Especially when you have nitpicky players.