knee-jerk reaction

plural knee-jerk reactions

1. idiomaticAn instantaneous reaction made without thought.

   Near-synonym: gut reaction

   1 more example

   But does the level crossing really need upgrading? Listening to Prosser, one gets the impression that this need to 'upgrade' is almost a kneejerk reaction. Although it is manually operated, Prosser thinks that the crossing is "pretty safe as it is", especially given the levels of traffic on the line. The signage, he says, could definitely be improved. But this relationship between who is responsible, either Network Rail or the local/road authorities, has long been a bone of contention. "In my experience, there's always a 'not my problem' attitude," he observes.

   2026 April 1, Richard Foster, “Fenland bridge "not safe"”, in RAIL, number 1058, page 33

   Synonyms: gut reaction