Historical clue formulations

• Sedative in a zookeeper's dart, informally — 2026-03-25
• Sedative, for short — 2022-07-14
• Sedative in a blowgun dart, informally — 2022-03-30
• Slangy sedative — 2020-09-12
• One delivering a knockout, informally — 2014-12-20
• Drug that calms the nerves, slangily — 2009-03-30