Wiktionary
megamillionaire
n. A person who has many times more than one million units of the local currency, but who is not a billionaire.
Usage examples of "megamillionaire".
With the help of his overweight megamillionaire neighbor--the Squidley of the title --Tom sets out to use the machine for the good of humanity, with all sorts of unintended consequences.
All he wanted to do was to build and sell EncryptionLok-3s, but if other Southern California megamillionaires were using first names, he would too.