IPA: /ˌmɪl.jəˈnɛr.ɪs/
KK: /mɪlˈjʊnɛrɪs/
A woman who has more than one million dollars or the equivalent in another currency.
She became a millionairess after her successful business venture.
Millionairess → It is formed from "million" (from Middle French *million*, meaning a thousand thousands) and "-ess" (a suffix used to denote female gender). The word "millionairess" refers to a woman who possesses a million or more in wealth.
Think of a woman who has a lot of money, specifically a 'million' — the suffix '-ess' indicates that she is female. This helps you remember that a millionairess is a wealthy woman.