-eaux is a common ending for historically Cajun surnames like Babineaux, Boudreaux, Breaux, Marceaux, Robicheaux and Thibodeaux, amongst others. Despite its somewhat confusing appearance, this combination of letters is pronounced with a long "O" sound (IPA: /oʊ/).

What does the suffix eaux mean?

Definition of "eaux" [eaux]

"In the French language, the suffix "eaux" - pronounced "O" - denotes the plural form of a word ending in "eau," like chateaux." "I feel the same way when people mock the GEAUX Tigers slogan as "eaux" is a common ending for many Cajun surnames so I just have to write it off to ignorance."

Why does eaux make an O sound?

The French letter combinations "​au" (singular) and "aux" (plural) are pronounced exactly the same way. ... When pronouncing the sound, the lips are pursed to actually form the shape of an "o." This physical component is key to correct French pronunciation.