1. superlative form of acerb; most sour or bitter in taste
2. superlative form of acerb; most harsh, severe, or sharp in manner or tone

Examples

• The acerbest lemon in the bunch made her pucker immediately.
• His acerbest comments during the meeting left everyone uncomfortable.
• She had the acerbest wit of anyone in the room, always ready with a cutting remark.
• The acerbest critic gave the film a scathing one-star review.
• That was the acerbest tone I've ever heard from him.
• The acerbest grapes were unsuitable for the wine.
• Her acerbest remarks were directed at the policy itself, not the people involved.