not tractable; difficult to manage or mold; "an intractable disposition"; "intractable pain"; "the most intractable issue of our era"; "intractable metal"
harshly uninviting or formidable in manner or appearance; "a dour, self-sacrificing life"; "a forbidding scowl"; "a grim man loving duty more than humanity"; "undoubtedly the grimmest part of him was his iron claw"- J.M.Barrie
a United States coin worth one twentieth of a dollar
five dollars worth of a drug; "a nickel bag of drugs"; "a nickel deck of heroin"
a hard malleable ductile silvery metallic element that is resistant to corrosion; used in alloys; occurs in pentlandite and smaltite and garnierite and millerite
any small or medium-sized cat resembling the domestic cat and living in the wild
(of a mine or oil well) drilled speculatively in an area not known to be productive; "drilling there would be strictly a wildcat operation"; "a wildcat mine"; "wildcat drilling"; "wildcat wells"
outside the bounds of legitimate or ethical business practices; "wildcat currency issued by irresponsible banks"; "wildcat stock speculation"; "a wildcat airline"; "wildcat life insurance schemes"