Although it is sometimes considered an adverb, best is virtually synonymous with should in We best be going, and ought to in We best go. Should and ought are auxiliary verbs. the best effort that a person, group, or thing can make: Their best fell far short of excellence. a person's best wishes or kindest regards: Please give my best to your father. Learn how to live more sustainably, discover the latest must-have electronics and explore what best fits your lifestyle, home, workspace and everything in between. 1. In a most excellent way; most creditably or advantageously. 2. To the greatest degree or extent; most: He was certainly the best hated man in the ship (W. Somerset Maugham). BEST definition: of the highest quality, excellence, or standing. See examples of best used in a sentence. At Best Buy Fullerton, we specialize in helping you find the best technology to enrich your life. Together, we can transform your living space with the latest smart home technology, HDTVs, computers and gaming consoles from your favorite brands. Shop at Best Buy for computers and tablets. Find laptops, desktops, all-in-one computers, monitors, tablets and more. In the best of all possible worlds, no one would be without food and clean water. I have a wonderful family and a great job, so I feel that I have the best of both worlds. best adjective, adverb (HIGHEST QUALITY) of the highest quality, to the greatest degree, in the most effective way, or being the most suitable or pleasing; superlative of good orwell: Use the Best Buy store locator to find stores in your area. Then, visit each Best Buy store's page to see store hours, directions, news, events and more.