penta-millionaire
n.— «There’s also been a steep rise in the number of what Phoenix refers to as “penta-millionaire” households—those with at least $5 million in liquid assets. There are now 755,000 of them, up 47 percent since 2003.» —“Mixed Blessings” by Mark Dolliver Adweek Feb. 26, 2007. (source: Double-Tongued Dictionary)