Edema or Oedema? Which One is the Correct Spelling?

Both are correct.

From Twitter:

Joshua Schwimmer
KidneyNotes Just overheard someone use the word "oedema" -- and they pronounced the "o." Oawesome.

BiteTheDust @KidneyNotes "use the word "oedema" -- and they pronounced the "o." Oawesome." perhaps they came from an English speaking country? ;-)

DrGourmet @AllergyNotes I always thought it was a contraction for "Oh! I have edema."

Edema (American English) or Oedema (British English), formerly known as "dropsy" or "hydropsy," is an abnormal accumulation of fluid beneath the skin, or in one or more cavities of the body. Source: Wikipedia.

Technically, the Greek origin of the word requires "oe-" for correct spelling. There are many medical terms that differ between American and British English, for example: anaemia, oesophagus, haemorrhage, haemophilia, etc.


  1. Those who know German, know even more. The "oe" is pronounced the same way as the letter o with dots on top. Ö (I wish I saw how all your machines print it!). Before the WWII German was a prominent language in medicine and e.g. in Scandinavian countries where this particular letter Ö is in use the terms with "oe" were adopted in German form, in this case (das) Ödem. In Finland this means that the terms originating from Greek is "oedema", from German "ödeema" and "ödeemi" and from the English speaking world term "edeema". And here comes the funny part of my comment - in Finnish it is simply "turvotus".

  2. Amazing! Good to know. Thanks for sharing.

  3. I'm a copyeditor by trade and work on medical journals, so spend a lot of time thinking about this kind of thing! Lots of the extra vowels in English spellings of medical terms are essentially silent anyway, e.g. oestrogen.

    I still prefer the British English versions, mostly through misplaced patriotism I think!

  4. I also like the British versions better, mostly because they are closer to the Greek "originals."

    Thank you for the comments.