1 [uncountable] literary or formal
great danger, especially of being harmed or killed
They put their own lives in peril to rescue their friends.
The economy is now in grave peril.
a voyage that was fraught with peril (=full of danger)
2 [countable usually plural] literary or formal
a danger or problem in a particular activity or situation:
the perils posed by mountaineering
the perils of the sea
used to say that what someone is intending to do is dangerous or could cause them problems:
Politicians ignore this issue at their peril.