How to pronounce AFFIDAVIT. How to say AFFIDAVIT.Affidavit definition: . See examples of AFFIDAVIT used in a sentence. The term is pronounced as "afuhDAYvit. " Breaking it down: "af" as in "after," "uh" as in "umbrella," "DAY" with emphasis, and "vit" rhymes with "fit." A written statement that someone makes after promising officially to tell the truth. An affidavit can be used as proof in a law court. How to say affidavit in English? Meanings, etymology, pronunciation and more in the Oxford English Dictionary.