A "zombie" bank is one that is artificially kept alive by a government bailout, when it otherwise would have died (failed).   In the strictest definition it is a bank with a market worth of less than zero. The term zombie bank or zombie firm was first used to describe failing businesses propped up by the Japanese government during a period of economic stagnation in Japan in the 1990s (called "the lost decade"). The strategy led to a bubble and consequent collapse, in part because the capital injections were not big enough to fix the system. 
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- Wall Street Voodoo. The New York Times.
- Back to Business with Emmet Oliver - Anglo peers into zombie bank land. The Sunday Tribune (Ireland).
- Obama: "Send Me A Bill That Creates or Saves 4 Million Jobs". The Nation.
- When bailed-out banks turn to zombies. Marketplace (American Public Media).