-Usage of resources to maximise the production of goods and services.
-Achieving maximum productivity with minimum wasted effort or expense.
-Using minimum time to complete maximum productivity.
-Reducing the amount of energy used to do something.
-Measure of output from a production process, per unit of input.
-Amount of work done in a particular period of time.
-The condition of being protected against physical, social, spiritual, financial, political, emotional, occupational, psychological, educational or other types of consequences of failure, damage, error, accidents, harm or any other event which could be considered non-desirable.
-Deals with the nature of beauty, art, and taste, and with the creation and appreciation of beauty.
-Closely related with the philosophy of art.
-Studies new ways of seeing and perceiving the world.
-Relies on our ability o discriminate at a sensory level.
-A state of physical ease and freedom from pain or constraint.
-Consolation for grief and anxiety.
-Something that gives satisfaction to its user.
Reference from: www.wikipedia.org and www.wiktionary.com