millionairess
From Longman Dictionary of Contemporary Englishmillionairessmil‧lion‧air‧ess /ˌmɪljəˈneərɪs $ -ˈner-/ noun [countable] old-fashioned RICHa woman who is very rich and has at least a million pounds or dollarsExamples from the Corpusmillionairess• Possibly even more so than being the all singing, all dancing performer which made her a millionairess.