efficacious (2009-08-14)

Part of Speech: adjective

Pronunciation: [ef′i kā′s̸həs]

Definition: Producing or capable of producing the desired effect; having the intended result; effective an efficacious drug.

Usage: If moral action is not efficacious in the production of moral good, then it may decrease the net amount of potential good.

Suggested Usage: (1) The aim of the new study is to find the most efficacious treatments for the disease. (2) For the previous twenty years the NHS had lost interest in hydrotherapy using natural mineral waters, believing that tap water was equally efficacious.

Etymology: Latin efficax (genitive efficacis) from efficere, to bring to pass, accomplish (see effect) + -ous.