Of the point (in temperature, reagent concentration etc.) where a nuclear or chemical reaction becomes self-sustaining.
Inclined to find fault or criticize.
Relating to criticism or careful analysis, such as literary or film criticism.
Of a patient condition involving unstable vital signs and a prognosis that predicts the condition could worsen; or, a patient condition that requires urgent treatment in an intensive care or critical care medical facility.
Likely to go out of control if disturbed, that is, opposite of stable.
Extremely important.
Of a temperature that is equal to the temperature of the critical point of a substance, i.e. the temperature above which the substance cannot be liquefied.
Pertaining to, or indicating, a crisis or turning point.
A critical value, factor, etc.
In breakdancing, a kind of airflare move in which the dancer hops from one hand to the other.
That operates to produce an effect.
Any of a class of behaviors that produce consequences by operating (i.e., acting) upon the environment.
An operative person or thing.