Latin in Medical ENglish

Latin in Medical English

Plain English Equivalents

When learning Medical English, students often come across Latin phrases that are still commonly used in hospitals, clinics, and academic papers. However, many of these expressions now have plain English equivalents. In this post, you’ll find out 10 frequently used Latin expressions and their modern English counterparts. Don’t miss it if you’re preparing for medical studies or if you have English speaking patients.

English Equivalents of Latin Expressions in Medical English

Latin	English
per os Take 1 tablet per os, once daily.	by mouth Take 1 tablet by mouth, once daily.
“Per os” may appear in prescriptions or academic writing, but “by mouth” is clearer in clinical use.
prn (pro re nata) Administer morphine 5 mg IV prn for pain.	as needed Administer morphine 5 mg intravenously as needed for pain.
“PRN” is common in records, but “as needed” works better in conversation and explanations.
stat(im) Give epinephrine stat!	immediately Give epinephrine immediately!
“Stat” is still widely used in emergencies. Use “immediately” in general communication.
tid (ter in die) Prescribe 500 mg amoxicillin tid.	three times a day Prescribe 500 mg amoxicillin three times a day.
Latin dosing abbreviations are still common but may confuse non-specialists. Use plain English when possible.
NPO (nil per os) The patient is NPO after midnight.	nothing by mouth The patient should have nothing by mouth after midnight.
“NPO” is still used in charts. Use the English form in patient instructions or team communication.
post mortem A post mortem examination was ordered.	after death An autopsy was performed after death.
“Post mortem” appears in legal/academic texts. “Autopsy” is more commonly used in modern clinical English.
in vitro The drug was tested in vitro before trials.	in the lab The drug was tested in the lab before trials.
Still used in research. Simplified versions help non-specialists understand findings.
in vivo The treatment showed promise in vivo.	in the body The treatment worked well in the body.
Like in vitro, still valid in academic English. Use casual terms when speaking with patients.
etiology The etiology of the illness is unclear.	cause The cause of the illness is unclear.
Common in textbooks. “Cause” is preferred for clarity. Useful in both spoken and written Medical English.
ex juvantibus Diagnosis was made ex juvantibus.	based on treatment The diagnosis was based on the patient’s response to treatment.
Rare in modern usage. Stick with the English version to avoid confusion.
contraindication There is a contraindication for this drug.	reason not to use There’s a reason not to use this drug.
Still widely used, but knowing the plain English version helps in clearer patient communication.

English Equivalents of Latin Expressions in Medical English

Latin	English	Sentence with Latin	More Casual Sentence	Notes
per os	by mouth / orally	Take 1 tablet per os, once daily.	Take 1 tablet by mouth, once daily.	“Per os” may appear in prescriptions or academic writing, but “by mouth” is clearer in clinical use.
prn (pro re nata)	as needed / when necessary	Administer morphine 5 mg IV prn for pain.	Administer morphine 5 mg intravenously as needed for pain.	“PRN” is common in records, but “as needed” works better in conversation and explanations.
stat(im)	immediately / at once	Give epinephrine stat!	Give epinephrine immediately!	“Stat” is still widely used in emergencies. Use “immediately” in general communication.
bid / tid / qid	twice / three / four times a day	Prescribe 500 mg amoxicillin tid.	Prescribe 500 mg amoxicillin three times a day.	Latin dosing abbreviations are still common but may confuse non-specialists. Use plain English when possible.
NPO (nil per os)	nothing by mouth	The patient is NPO after midnight.	The patient should have nothing by mouth after midnight.	“NPO” is still used in charts. Use the English form in patient instructions or team communication.
post mortem	after death / autopsy	A post mortem examination was ordered.	An autopsy was performed after death.	“Post mortem” appears in legal/academic texts. “Autopsy” is more commonly used in modern clinical English.
in vitro	in the lab	The drug was tested in vitro before trials.	The drug was tested in the lab before trials.	Still used in research. Simplified versions help non-specialists understand findings.
in vivo	in the body	The treatment showed promise in vivo.	The treatment worked well in the body.	Like in vitro, still valid in academic English. Use casual terms when speaking with patients.
etiology	cause	The etiology of the illness is unclear.	The cause of the illness is unclear.	Common in textbooks. “Cause” is preferred for clarity. Useful in both spoken and written Medical English.
ex juvantibus	based on response to treatment	Diagnosis was made ex juvantibus.	The diagnosis was based on the patient’s response to treatment.	Rare in modern usage. Stick with the English version to avoid confusion.
contraindication	reason not to use a treatment	There is a contraindication for this drug.	There’s a reason not to use this drug.	Still widely used, but knowing the plain English version helps in clearer patient communication.

Final Thoughts

Whether you’re studying English for Medical Students or preparing for an international placement, learning how to say things in straightforward English is just as important as mastering clinical vocabulary. We hope this overview helps you feel more confident in both traditional and modern terminology typical for English in Medicine. Bookmark this page and share it with friends.

If you’re looking for teacher-guided lessons and courses in Medical English, write to us at biuro@learner.com.pl. We teach doctors, nurses, and healthcare students.

All the best!

Learner Team