Solvent’s meaning changes pretty drastically depending on its part of speech. As a noun, solvent is either a certain kind of chemical or an idea that solves a problem. As an adjective, solvent describes someone who's got cash on hand.
A solvent dissolves other chemicals, which is why it's also easy to remember: solvent is a chemical used to dissolve other chemicals. The adjective solvent, on the other hand, comes from a French verb that means "loosen." In these tough economic times, only those banks that are solvent are in a position to loosen the cash flow and start lending money. No cash? You're not solvent.