Definition from Wiktionary, the free dictionary
Middle English contraction of perilous
- Rhymes: -ɑː(r)ləs
- Attended with peril; dangerous; risky.
- The situation became parlous when the weather made resupply impossible.
- Dire, terrible, appalling.
- Those manning the facility were in a parlous state.
- (obsolete) Dangerously clever or cunning.
Derived terms 
parlous (not comparable)