perilous
adjectiveUK /ˈper.əl.əs/
US /ˈper.əl.əs/
Very dangerous and likely to cause harm.
The hikers crossed the perilous bridge over the deep river.
OTHER MEANINGS
2. Full of great risk or uncertainty.
They began a perilous journey through the mountains.
3. Likely to cause serious problems or failure.
The company is in a perilous financial situation.
4. Exposed to the chance of being harmed or lost.
The small boat sailed into perilous waters.