Learner's definition of CRITICAL
1 [more critical; most critical] : expressing criticism or disapproval 2 : of or relating to the judgments of critics about books, movies, art, etc.
The book received much critical acclaim. [=many critics said good things about the book]
The movie was a critical success [=critics liked the movie], but it didn't make much money.
3 : using or involving careful judgment about the good and bad parts of something
The program presents a critical analysis of the government's strategies.
She has a talent for critical thinking.
We need to look at these proposed changes with a critical eye before we accept them.
4 [more critical; most critical] : extremely important
We have reached a critical phase of the experiment.
It is absolutely critical [=vital, essential] for us to remain together.
This is a matter of critical importance to the future of our country.
5 [more critical; most critical], medical : relating to or involving a great danger of death
— sometimes used figuratively
He suffered critical injuries in the accident.
The patient is in critical condition. = The patient is critical. [=the patient is very sick or injured and may die]
a nurse who specializes in critical care [=the care of patients who are in critical condition]
patients who are on the critical list