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Synonyms for Wildcat (same or very similar meaning)

WordNet sense 1 (a cruelly rapacious person):
beast, brute, savage, wolf

WordNet sense 2 (an exploratory oil well drilled in land not known to be an oil field):
wildcat well

WordNet sense 3 (not sound financially):

WordNet sense 4 (without official authorization):
unauthorized, unauthorised

WordNet sense 5 (not having official authority or sanction):

WordNet sense 6 (serving in or intended for exploration or discovery):
exploratory, explorative

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