adv. phr. 1. Under the best conditions; as the best possibility. A coal miner's job is dirty and dangerous at best. We can't get to New York before ten o'clock at best.
Compare: AT MOST.
Antonym: AT WORST. 2. In the most favorable way of looking at something; even saying the best about the thing. The treasurer had at best been careless with the club's money, but most people thought he had been dishonest.