dysfunctional

This term describes a failure of a system or relationship to achieve its intended purpose, carrying a strong connotation of instability and breakdown. When applied to mechanical or organizational systems, it suggests a technical or structural failure that prevents efficiency. It is often used in professional or clinical contexts to describe a lack of coordination or a systemic glitch.

In a psychological or social context, the word specifically targets the toxic dynamics of a family or group. It implies a pattern of behavior that is not just occasionally problematic, but chronically unhealthy and damaging to the individuals involved. It is more severe than calling a relationship "strained" or "difficult," as it suggests a fundamental deviation from healthy functioning.