The use of the word "optimize" dates back to 1857 in English and it means "to make as perfect, effective, or functional as possible". The word "optimization" was derived from "optimize" and means "an act, process, or methodology of making something (as a design, system, or decision) as fully perfect, functional, or effective as possible ; specifically : the mathematical procedures (as finding the maximum of a function) involved in this". The words "optimum", "optimize", "optimism", "optimist", "optimal", and "optimization" are all related were derived from each other at some period of time. I can refer more interested people to Online Etymology Dictionary.
That's enough with the etymology of the "optimization" related words. Let's come back to today and see how it is used. OR people know the meaning of the word "optimization" by their heart, "the study of problems in which one seeks to minimize or maximize a real function by systematically choosing the values of real or integer variables from within an allowed set".
Apparently, there is a small difference in understanding this definition between OR people and people from other disciplines. Especially, the most difficult times to communicate between happens when an OR academician faces a non-OR industry person and tries to talk about about "optimizing" a system. The word "Optimal" means "the best with respect to a defined system" for an OR specialist, while it sounds more like "acceptably better" for an industry expert. It is an ironic representation of misevaluation of OR among the industry. It puts a responsibility to the shoulders of operations research experts and industrial engineers that they should devote some of their energy to tell what they are doing for science, for industry, and for life itself in general for an average person can understand well in a cople of minutes. Actually, there are very nice OR definitions that says what it means in a couple of very clear sentences but communicating the messag these definitions mean is a life-long struggle. It might be really good to take start with explaining what "optimal" means to a non-OR colleague of ourselves clearly and making sure he does not forget it by practicing it "optimally" at our work and research.