How do you spell Rammer

Available Definitions:
1)  n. - One who, or that which, rams or drives.
2)  n. - An instrument for driving anything with force; as, a rammer for driving stones or piles, or for beating the earth to more solidity
3)  n. - A rod for forcing down the charge of a gun; a ramrod
4)  n. - An implement for pounding the sand of a mold to render it compact.