1. (adj)unable (usually followed by `to') not having the necessarymeans or skill or know-how "unable to get to town without a car"; "unable to obtain funds"
2. (adj)unable(p) (usually followed by `to') lacking necessary physical or mental ability "dyslexics are unable to learn to read adequately"; "the sun was unable to melt enough snow"
3. (adj)ineffective, ineffectual, unable lacking in power or forcefulness "an ineffectual ruler"; "like an unable phoenix in hot ashes"