IPA: /ˈpɛrɪləsnəs/
KK: /ˈpɛrɪləsnəs/
The state of being dangerous or risky, often involving a threat to safety or well-being.
The perilousness of climbing without proper gear can lead to serious accidents.
Perilousness → It is formed from "peril" (from Old French *peril*, meaning danger) and "-ous" (meaning full of) and "-ness" (meaning the state of). The word "perilousness" means the state of being full of danger or risk.
Think of 'peril' meaning danger, and remember that 'perilousness' describes the state of being full of danger.