Answer:

octuple

Answer	Crossword Clue
OCTUPLE	Eightfold
OCTUPLE	Double x double x double
OCTUPLE	Eight times as great

OCTUPLE	Double, double and double again
OCTUPLE	Consisting of eight parts.
OCTUPLE	Eightfold.
OCTUPLE	Like an amazing return on an investment
OCTUPLE	Expand to 800%