the speech act of answering an attack on your assertions; "his refutation of the charges was short and persuasive"; "in defense he said the other man started it"
being in effect or operation; "de facto apartheid is still operational even in the `new' African nations"- Leslie Marmon Silko; "bus service is in operation during the emergency"; "the company had several operating divisions"
of or intended for or involved in military operations
pertaining to a process or series of actions for achieving a result; "operational difficulties"; "they assumed their operational positions"
marked by qualities giving the power to produce an intended effect; "written propaganda is less efficacious than the habits and prejudices...of the readers"-Aldous Huxley; "the medicine is efficacious in stopping a cough"
(usually followed by `of') having capacity or ability; "capable of winning"; "capable of hard work"; "capable of walking on two feet"
(followed by `of') having the temperament or inclination for; "no one believed her capable of murder"
possibly accepting or permitting; "a passage capable of misinterpretation"; "open to interpretation"; "an issue open to question"; "the time is fixed by the director and players and therefore subject to much variation"