Definition of "efficaciousness" [ef•fi•ca•cious•ness]

• The capacity or power to produce a desired effect. (noun)

Gnu Collaboartive International Dictionary of English: licensed under The Code Project Open License (CPOL)

• "The efficaciousness of the D&R approach is evident throughout "The Sorcerers and Their Apprentices.""
• "I think media spin is overrated – which is why the good Charlie Cook always makes me sigh – what matters is the efficaciousness of the policies."
• "The cold formality and dread-inducing, proto-Nurse-Ratched efficaciousness of this convocation affords a chilling counterbalance to the vulnerability implied in the prisoner portraits."