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. Shop Best Buy for electronics, computers, appliances, cell phones, video games & more new tech. Store pickup & free 2-day shipping on thousands of items. 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. Idioms (all) for the best, producing good as the final result: It turned out to be all for the best when I didn't get that job. Idioms as best one can, in the best way possible: As best I can tell, we're the first ones here. Best definition: Surpassing all others in excellence, achievement, or quality; most excellent. 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. 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 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: BEST definition: of the highest quality, excellence, or standing. See examples of best used in a sentence. You should wear your best clothes tonight. He took us to the (very) best restaurants in the city. We ate the best food and drank the best wines.