Definition of "Wildcat" :

noun: any small or medium-sized cat resembling the domestic cat and living in the wild

noun: an exploratory oil well drilled in land not known to be an oil field

noun: a cruelly rapacious person

adjective: (of a mine or oil well) drilled speculatively in an area not known to be productive

"Drilling there would be strictly a wildcat operation."

adjective: without official authorization

"Wildcat work stoppage."

adjective: outside the bounds of legitimate or ethical business practices

"Wildcat currency issued by irresponsible banks."