double

noun

1.
a base hit on which the batter stops safely at second base
two-bagger two-base hit two-baser
Derived from:
double
2.
a stand-in for movie stars to perform dangerous stunts
3.
someone who closely resembles a famous person (especially an actor)
evil look-alike ill-boding look-alike twiganger image look-alike
4.
a quantity that is twice as great as another
doubleness two times
Derived from:
double double
5.
raising the stakes in a card game by a factor of 2
doubling
Derived from:
double double