-dex is a suffix used by: (1) André Joyce for the operand 510, a verbalized Roman numeral DX, as in the number name (arithmonym), googodex = g(2, 1020, 510). This was re-spelled with the silent -h- infix for "formerly high", to -dhex to distinguish it from the secondary meaning. googol (2) -dex is also a suffix exclusive to ExE designed by Sbiis Saibian. Let N be a number expressed in ExE as Ea@. In this case (N)-dex = Ea#N. With this Sbiis Saibian forms several derivative googolisms. Examples: googol = E100 --> googoldex = E100#(E100) = E100#1#2 = E100,000#100,000#2