Etymology of "Rx"

A. Maberry maberry at U.WASHINGTON.EDU
Thu Nov 11 18:49:44 UTC 1999

This hardly sets the record straight, but I have always heard that it is
an abbreviation for some form the Latin verb recipio -ere. The "R" is
understandable and the "x" is a medieval Latin ligature for a combination
of letters which forms the abbreviation "Rx". The "x" sign probably
doesn't represent an "x" since Latin only uses an "x" to represent the
Greek letter "ksi" in Greek loan words.
I also doubt the bit about Juppiter since the Roman god of medicine was
Aesculapius (from Greek Asklepios), and one would think that it would be
him who would be invoked to bless medicine (him, or perhaps Apollo Medicus
(cf. Latte. Roemische Religionsgeschichte).
I can probably provide a less speculative answer tomorrow when I get back
to campus.

There are a number of examples of medieval letters, or forms of letters
have been misinterpreted in modern times, the most common being "Ye olde
..." where the Y represents the obsolete (in English anyway) character the
thorn (="th"). I remember hearing or reading somewhere that French plurals
ending in -x go back to the fact that in old French handwriting the final
-s had the shape of something like an -x and that it is now just
orthographic convention to write -x for -s--but someone on this list MUST
no more about French than I do, and if I'm completely off base, I hope
they will set me straight.

maberry at

On Thu, 11 Nov 1999 MARYPROTO at AOL.COM wrote:

> I edit a newsletter called Copy Editor, and one of our columnists has
> submitted an article in which he writes:
> "What about the origin of 'Rx'? It may have been an abbreviation of the Latin
> _recipe,_ meaning 'take,' or a representation of the sign for Jupiter, which
> 'Rx' vaguely resembles. The sign on ancient prescriptions invoked the deity's
> blessing on the medicine."
> Every dictionary I've checked gives only the Latin "recipe" in the etymology
> of "Rx" (if the dictionary lists "Rx" at all). I told the writer, who then
> faxed me an article from FDA Consumer Magazine, which says:
> "Where does the 'Rx' for 'prescriptions' come from? Its origins are given
> variously as an abbreviation of the Latin word 'recipe,' meaning 'take,' or
> as a representation of the astrological sign of Jupiter [SIGN HERE]. This
> sign was placed on ancient prescriptions to invoke that deity's blessing on
> the medicine to help the person get well. More recently, the cross at the end
> of the 'R' has been explained as a substitute period."
> I'm suspicious of the Jupiter connection, not only because of the source of
> the information but also because the planet's sign looks nothing like "Rx."
> Can anybody set the record straight for me? Many thanks.
> Mary Beth Protomastro
> Editor and Publisher
> Copy Editor: Language News for the Publishing Profession
> marybeth at or maryproto at

More information about the Ads-l mailing list