critical
crit-i-cal
adjective
Involving careful analysis and evaluation to form a reasoned judgment.
"Develop your critical thinking skills."
adjective
Extremely important or serious, determining the outcome of something.
"The patient is in a critical condition."
adjective
Expressing disapproval or finding fault with something or someone.
"She was very critical of his new plan."
Thesaurus
Synonyms: censorious, overcritical, vituperative, captious, searing, scathing, hypercritical, deprecative, faultfinding, desperate, serious, dangerous
Antonyms: noncritical, noncrucial, uncritical