銭

1. noun sen (hundredth of a yen)
2. coin made of non-precious materials
3. obsolete one-thousandth of a kan (as a unit of currency)
4. archaic one-thousandth of a kan (as a unit of mass)

ぜに

1. noun, colloquial round coin with a (square) hole in the center
2. coin made of non-precious materials
3. money

ぜぜ

1. noun, children's language money