critical

Critical is an English adjective with several related meanings stemming from the idea of discernment, judgement, and urgency. It can describe evaluation and judgment, seriousness or danger, or pivotal moments in a process. The term also appears in specialized technical uses in science and medicine.

In everyday language, critical often means tending to find fault or expressing disapproval: a critical review. It can also describe careful examination and judgment: critical thinking, critical analysis. In journalism or appraisal, a critical stance involves weighing evidence and arguments rather than taking statements at face value.

In medical context, critical condition describes life-threatening illness or injury. In science and engineering, critical has technical senses: critical point in thermodynamics is the condition at which distinct liquid and gas phases cease to exist; critical temperature and critical pressure are the corresponding parameters; the term also appears in discussions of critical mass, critical path in project management, and critical load in structural engineering.

Etymology: from Greek kritikos, via Latin criticus, meaning able to discern; the English sense of evaluation and judgment developed through medieval and modern usage. Related forms include critical, critique, criticism, and hypercritical.