fiance / fiancee are similar-sounding terms with different meanings (referred to as homophones). To better understand the differences, see below for definitions, pronunciation guides, and example sentences using each term. 👇
fiance: (noun) a man who is engaged to be married.
fiancee: (noun) a woman who is engaged to be married.
fiance: f·iy·AA·n·s·EY
fiancee: f·iy·AE·n·s·iy
(Examples are Wikipedia snippets under the CC ShareAlike 3.0 license. Definitions drawn from WordNet.)