critical circumstances; risky conditions; danger zone

dangerous; sinister; vicious

narrowly; almost; nearly

evil omen

(of terrain) rugged, providing a natural barrier to invasion

perilous peak; the lofty heights

(of terrain) mountainous; rugged; (of a situation) precarious; daunting

peril; dangerous circumstance

shoals; rapids; treacherous section of a river

dangerous ball (in soccer, volleyball etc)

critical illness

insurance type

to win by a narrow margin

strategically situated and easy to defend; strategic location

sinister and deceitful

dangerous and difficult (path)

dangers spring up all around (idiom); surrounded by perils