taste blood

taste blood (third-person singular simple present tastes blood, present participle tasting blood, simple past and past participle tasted blood)

1. (figuratively) To sense weakness in another, encouraging one to attack.
   • 1968 January, Henry S. Resnik, “Passion on a Bicycle”, in The Atlantic‎^[1], →ISSN, archived from the original on 6 December 2022:

     […] in those few moments I had proved myself a cyclist of such enormous cool, such dazzling technique, that I knew I would never again slow down for an advancing truck, veer to avoid a threatening limousine, or hesitate to plunge into the midst of a pedestrian phalanx. I had tasted blood, and now I knew what all those pillar-legged hostelers felt as they sat around their campfires, recalling the encounters and skirmishes of the day.

   • 2012 July 14, Matt Williams, Ewen MacAskill, “Obama repeats attack on Romney as 'pioneer of outsourcing'”, in The Guardian‎^[2], →ISSN, archived from the original on 8 June 2018:

     But having tasted blood on the issue, the Obama campaign kept jabbing away.

2. (figuratively) To press home an advantage in a debate, etc.
3. (figuratively, by extension) To take pleasure in something new.

• “taste blood”, in Collins English Dictionary.