perilous

Adjective

• fraught with danger
  • dangerous waters
    
  • a parlous journey on stormy seas
    
  • a perilous voyage across the Atlantic in a small boat
    
  • the precarious life of an undersea diver
    
  • dangerous surgery followed by a touch-and-go recovery
    

Related words

• Synonyms: 
  parlous , precarious , touch-and-go