How to say "prescription" in Japanese

Choosing the right word

規定きていJLPT N1approx.Common
noun, suru verb, transitive verbHere 'prescription' means a formal stipulation or provision — a rule laid down in regulations or law. It never refers to medicine or to legal time limits.
この犯罪はんざいに対たいして法律ほうりつはある罰則ばっそくが規定きていされている。↗
The law prescribes certain penalties for this offence.
処方しょほうCommon
noun, suru verb, transitive verbThe medical sense: the prescribing of medicine, or the formula prescribed. It denotes the act or content of prescribing; the written document itself is 処方箋.
医者いしゃは患者かんじゃに薬くすりを処方しょほうした。↗
The physician prescribed his patient some medicine.
時効じこうCommon
nounThe legal term: prescription as in acquisitive or extinctive prescription — rights acquired or extinguished with the passage of time; broadly, the statute of limitations. It is never a medical prescription.
処方箋しょほうせんCommon
nounThe written prescription itself: the slip a doctor issues, taken to a pharmacy to have the medicine dispensed. When English 'prescription' means the piece of paper, this is the word.
処方箋しょほうせんをもらうために医者いしゃに行いきなさい。↗
Go to the doctor to get your prescription!

For medicine, choose 処方 for the prescribing or formula and 処方箋 for the written slip; 規定 means a formal stipulation or provision, while 時効 is the legal prescription by which rights are gained or lost with time.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

Japanese equivalents

規定きていstipulation
処方しょほうprescription (of medicine)
時効じこうstatute of limitations
処方箋しょほうせんprescription
薬方やくほうprescription
薬箋やくせんprescription
さじ加減さじかげんmeasured amount (esp. of medicine)
方書きほうがきprescription
レシピ(medical) prescription

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