Edit
Short for financial domination. A BDSM fetish or lifestyle where the submissive (called a "paypig") gives money or gifts to the dominant (the "findomme" or "money mistress"). Not to be confused with femdom.
Unlike prostitution the act of giving money is not transactional and nobody is "buying" sexual services. The dominant is either demanding money from the submissive or the submissive is willingly giving it to the dominant. It's BDSM involving money.