- full of risk; perilous; risky: a hazardous journey.
- dependent on chance.
Origin of hazardous
SynonymsSee more synonyms on Thesaurus.com
1. dangerous, unsafe. 2. chancy, uncertain, risky, speculative.
1. safe, secure. 2. sure, certain, reliable.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for hazardous
Refinery management had normalized the occurrences of hazardous conditions.Oil Tankers Leaking into Seattle’s Water
October 13, 2014
Warning: NSFW in places where facial spasms and eye moistness could be hazardous.Move Over, Ladies: Dove Does Dads
June 17, 2014
It's not fun to conduct a hazardous snatch of an insurgent leader, only to find you grabbed the wrong guy.Special Ops’ Weapons Wish List
April 9, 2014
And not knowing what could be in your genetic future is hazardous to your health.23andMe and Me: Why Policymakers Should Set the Genetic Testing Company Free
Charles C. Johnson
February 4, 2014
“There are still cars filled with gasoline,” said Sûreté du Québec Sgt. Michel Brunet about the hazardous scene.Inside the Brutal Clean-up Efforts in Lac-Megantic
July 16, 2013
Of all the hazardous ventures in which the detective had been engaged, this was certainly not the least hazardous.Henry Dunbar
M. E. Braddon
This is a strange and hazardous situation in which we are placed.Homeward Bound
James Fenimore Cooper
Wherever he had elected to crouch and tremble, it was too hazardous to go near him.Nostromo: A Tale of the Seaboard
The condition of his heart was hazardous and she had been told that any excitement might be fatal.The Paliser case
The descent was as anxious and hazardous as the ascent had been laborious.Ten Thousand Miles with a Dog Sled
- involving great risk
- depending on chance
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for hazardous
Online Etymology Dictionary, © 2010 Douglas Harper