Œ

Œ (minuscule: œ) is a Latin alphabet grapheme, a ligature of o and e. In medieval and early modern Latin, it was used to represent the Greek diphthong οι, a usage that continues in English and French. In French, it is also used in some non-Latin words.

It is used in the modern orthography for Old West Norse and is used in the International Phonetic Alphabet to represent the open-mid front rounded vowel. In English runology, œ is used to transliterate the Runic letter odal ᛟ , and so œ is sometimes called œthel, oethel or ethel (from ēðel 'estate, ancestral home').

In Latin, the combination denotes a diphthong, pronounced [oi̯], that had a value similar to English oi as in coil. It was used in borrowings from Greek words having the diphthong OI (ΟΙ, οι). Both classical and modern practice is to write the letters separately, but the ligature was used in medieval and early modern writings, in part because œ was reduced to a simple vowel ([e]) in late Latin.

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