wild·cat 
(wīldkăt′)
(wīldkăt′)n.
1. Any of various wild felines of small to medium size, including the bobcat and the caracal.
2. A small wild feline (Felis silvestris) of Eurasia and Africa, generally regarded as being the ancestor of the domestic cat.
3.
a. A quick-tempered person.
b. A person regarded as fierce.
4. An oil or natural-gas well drilled in an area not known to be productive.
5. A workers' strike unauthorized by their union.
adj.
1.
a. Risky or unsound, especially financially.
b. Issued by a financially irresponsible bank: wildcat currency.
c. Operating or accomplished outside the norms of standard, ethical business procedures: wildcat life insurance schemes.
2. Of, relating to, or being an oil or natural-gas well drilled speculatively in an area not known to be productive.
3. Undertaken by workers without approval of the officials of their union: a wildcat strike.
v. wild·cat·ted, wild·cat·ting, wild·cats
v.tr.
To prospect for (oil, for example) in an area supposed to be unproductive.
v.intr.
1. To prospect for oil or other minerals in an area not known to be productive.
2. To go out on an unauthorized labor strike.