What does “precarious” mean?
“Precarious” is an adjective meaning dangerous. It is usually used about a particular situation.
If I am walking in the middle of a busy road, I am in a precarious situation.
If I only have a small amount of money for the rest of the month, my finances are precarious.
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The linked adverb is “precariously”: When I am walking in the middle of the road, I am behaving precariously.