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.
Contrast: 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.