The Forgotten French Letter: Œ
Before we start, I would like to point out that the œ is not actually a letter in the sense that it’s not in the alphabet. It is, however, widely used in French, so it deserves its own post.
The œ doesn’t have an official name in French. It’s known as the “e dans l’o” (e in the o) or as the “o et e collés” (glued o and e).
It’s often followed by a u, like in the following words:
Mœurs — manners
Cœur — heart
Sœur — sister
Œuf — egg
Bœuf — beef
Œuvre — work
Vœu — wish
It isn’t always the case, however; œil (eye) is an example of a word in which œ isn’t followed by a u. Some place names, especially in Alsace-Lorraine, also use the œ without a u after it. In this case, the œ replaces the German ö. In all of these cases, it is pronounced /œ/ (same as eu in french, for those that can’t read IPA).
When œ isn’t followed by u (excepting the examples mentioned above), it pronounced /e/ (or like a é), like in œstrogène (estrogen). The plural of bœuf and œuf, bœufs and œufs, are pronounced like /ø/ (a cross between the french eu and u).
So you might wonder why it’s so important to write œ instead of oe, since after all, it’s the same letters (sort of), with the space being the only difference. The main reason is pronunciation. Oe is pronounced differently. It can either be pronounced /wa/ (same as oi), as is the case with poêle (frying pan) and moelleux (soft), or as separate vowels, as is the case with any words with an accent on the e (excepting ê) and any word beginning with co-, for example:
Poésie — poetry
Noël — Christmas
Poète — poet
Coefficient — coefficient
Œ is therefore a pretty useful letter in French, and it’s important to use it properly!