ENGLISH
REFERENCE

hazardous

adj.
US //ˈhæzɝdəs// UK //hˈæzədəs// haz·ardous
  1. 1 dangerous (adj.)
    B2 Upper Intermediate

    dangerous and likely to cause harm or an accident.

    involving great risk or danger, particularly in relation to physical safety or environmental health.

    Example

    The stairs were hazardous because they were covered in a thin layer of ice.

    Example

    The factory was forced to close temporarily after inspectors discovered that hazardous chemicals were being stored in leaking containers near the river.
  2. 2 involving chance (adj.)
    C2 Proficiency Archaic Literary

    depending on luck or chance rather than a plan.

    dependent on chance or fortune; unpredictable in nature.

    Example

    The traveler took a hazardous path through the woods, hoping for good luck.

    Example

    In the poet's view, life was a hazardous journey where one's fate rested entirely on the whims of fortune.

    Usage

    In modern English, this sense is almost entirely replaced by 'risky' or 'uncertain'.
Origin

From Middle French hasardeux, equivalent to hazard + -ous.

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