\ ˌär-ˈeks How to pronounce Rx (audio) \
plural Rxs

Definition of Rx

: a doctor's prescription also : something resembling a doctor's prescription in being an advisable or corrective course of action … rest is still the best Rx for pulled muscles. — Mara Grunbaum

Did You Know?

The "R" in "Rx" stands for the Latin word recipe, meaning "take," and the first doctor to use "Rx" used it as a verb with the same meaning, "Rx two aspirin" being equivalent to today's "Take two aspirin." (The word recipe had had the same function from the 13th through the 17th centuries.) Those two letters were a 19th-century take on a 16th-century symbol, the letter R with a line through its slanted leg-the line signaling that the "R" is functioning as an abbreviation. It wasn't till the early 20th century that "Rx" came to be used as the noun we know today. As for the noun "recipe," it followed the same trajectory, referring to a medical prescription for about 100 years before it developed its connection with cooking in the early 17th century.

First Known Use of Rx

1911, in the meaning defined above

History and Etymology for Rx

alteration of ℞, symbol used at the beginning of a prescription, abbreviation for Latin recipe, literally, take — more at recipe

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Cite this Entry

“Rx.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Rx. Accessed 14 Jul. 2020.

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How to pronounce Rx (audio)

English Language Learners Definition of Rx

US : a doctor's prescription


\ ˈär-ˈeks How to pronounce Rx (audio) \

Medical Definition of Rx

: a medical prescription

More from Merriam-Webster on Rx

Rhyming Dictionary: Words that rhyme with Rx

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