Just a hair

Language is one of the easiest forms of collecting.  It costs nothing, it is always rewarding, and discoveries come in the oddest places.  All that is required is the paying of attention.

Last week, I was in the hospital for a cardio angiogram which involves both injection of an unpleasant dye (causing a version of momentary hot flashes across your body) as well as the awkwardness of the rotating x-ray.  You lie prone and as still as possible while you are automatically slid into and out of the doughnut hole of a quietly whirring x-ray machine.  It is not a difficult procedure, merely mildly disconcerting.

Because it involves x-rays, you are alone in the room, just you and the doughnut CT scanner.  The technicians are in a room adjacent.  Occasionally a nurse might enter to make some adjustment.

As happened to me on this most recent visit.  I had already spent 10-15 minutes being slid in and out of the CT scanner, prone, still, holding, as instructed, my breath at various points.  The nurse entered to inject some other medication into my IV.  She explained:

We need to slow your heart down just a hair to get a better image.

I was aware of the possible issue, that above a certain heart rate, the x-ray imaging loses resolution and that there was an optimum heart beat which they aimed for via IV drugs.  

But in that antiseptic isolation, in the very maw of that medical technology, I took great pleasure in that "slow your heart down just a hair."  Perhaps it was the contrast between a loose hair and that cold, dark, sterile room and procedure.  Regardless, it sounded so human; "just a hair."  

I can't say when I first heard the term, "just a hair" to indicate a minute distance.  I can't say when I last heard someone use it, but thinking about it, I am not sure it hasn't been some years.  I am not sure when I even last read it in a text.  

I have a vague impression that it might be more of a rural term than urban.  Perhaps more dated than contemporary. 

I do an Ngram viewer comparing "just a hair" to two other idioms, "in a heartbeat", and "a dog's breakfast."  The first I assume to be widely known, the second less so.  And indeed, Ngram viewer has these about the ordinal ranking I would have assumed, with "just a hair" bouncing along at the bottom, on the verge of linguistic extinction, but hanging in there.

Maybe the Baader-Meinhof effect will kick in and I'll notice "just a hair" with some frequency over the next month or so, suggesting that I have been merely overlooking it.  

Regardless, "just a hair" in that warm Georgia drawl was a wonderful psychological lifeline back from the antiseptic isolation of modern medicine into the messy and delightful world of language.