Learner's definition of PRECARIOUS
[more precarious; most precarious]
not safe, strong, or steady
He earned a precarious livelihood/living by gambling.
She was in a state of precarious [=delicate] health.
The government is in a precarious position. [=a dangerous position that must be dealt with carefully]
The strong wind almost knocked him off of his precarious perch on the edge of the cliff.