The x in rx, fx, sx, tx...

Acrolect

Senior Member
German, Austria
There are various theories about why rx means 'prescription', some assuming that it has been derived from a symbol resembling this combination. But rx is not the only word used in a certain form of medical discourse (possibly the more practical and less theoretical side of medicine), but there is also fx 'fracture', sx 'symptom/s', tx 'therapy', dx 'diagnosis/diagnose'.

My question now is what the function of the x is? Is it possible that it has come to be used as the equivalent of a period (somehow in analogy to rx, even though it might not have had that function there originally), so that actually sx should be s.? This is the only explanation I could come up with since there does not seem to be any parallels between what the x could stand for otherwise (not a morpheme, not a syllable, not any specific combination of sounds/letters).
 
  • Thomas1

    Senior Member
    polszczyzna warszawska
    Here is what MW says about rx:

    They don't have the rest of the symbols, though.

    EDIT: Here is another theory about the wadjet eye (eye of Horus) origin of ℞.
    My junch is that the rest of the abbreviations might have been created by analogy to Rx.
     
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    lablady

    Senior Member
    English - USA
    While Rx has an accepted etymology, as far as I know the others are nothing more than standardized shorthand. The abbreviations are faster/easier for the doctors to write, and they make it easier for those of us who have to decipher what was written.

    Long, long ago when I was taught the abbreviations, I don't think I was ever told their origins. My medical dictionary is of no help, sorry.
     

    Acrolect

    Senior Member
    German, Austria
    Thanks a lot.
    I think it makes perfect sense that these abbreviations originated in the discourse of prescription. Given doctors' often idiosyncratic handwriting having an x instead of a period definitely benefitted legibility.

    I have got the impression that the abbreviations are more and more being used by laypersons in medical forums, partly morphologically integrated into the normal language system, e.g. in I was dx'ed with MS.
     
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