Lucre, from the Lat. lucrum, meaning gain in terms of money or wealth within the nation.
Often it is used in a negative, as in the phrase “not given to filthy lucre” from the Bible 1 Timothy 3:3.
From this, the term "filthy lucre" became slang for money.
The term is also the root of the word lucrative.
Read more about Lucre: In Fiction