Precarious
PRECA'RIOUS, adjective [Latin precarius, from precor, to pray or entreat; primarily, depending on request, or on the will of another.
1. Depending on the will or pleasure of another; held by courtesy liable to be changed or lost at the pleasure of another. A privilege depending on another's will is precarious or held by a precarious tenure.
2. Uncertain; held by a doubtful tenure; depending on unknown or unforeseen causes or events. Temporal prosperity is precarious; personal advantages, health, strength and beauty are all precarious depending on a thousand accidents.
We say also, the weather is precarious; a phrase in which we depart not more from the primary sense of the word, than we do in a large part of all the words in the language.