dangerous

adjective

dan·​ger·​ous ˈdān-jə-rəs 

ˈdān-jərs,

-zhrəs

1

: involving possible injury, pain, harm, or loss : characterized by danger

a dangerous job

2

: able or likely to inflict injury or harm

a dangerous man

dangerously adverb

dangerousness noun

Synonyms

• hazardous
• risky
• perilous
• serious
• unsafe

Choose the Right Synonym for dangerous

dangerous, hazardous, precarious, perilous, risky mean bringing or involving the chance of loss or injury.

dangerous applies to something that may cause harm or loss unless dealt with carefully.

soldiers on a dangerous mission

hazardous implies great and continuous risk of harm or failure.

claims that smoking is hazardous to your health

precarious suggests both insecurity and uncertainty.

earned a precarious living by gambling

perilous strongly implies the immediacy of danger.

perilous mountain roads

risky often applies to a known and accepted danger.

shied away from risky investments

Examples of dangerous in a Sentence

She got into a car accident while driving through a dangerous intersection.

He often drives at dangerous speeds.

The city can be a dangerous place to live.

The storms may cause dangerous flooding.

He is wanted for assault with a dangerous weapon.

the most dangerous of drugs

Recent Examples on the Web

Other symptoms can include itching, swelling, and a throbbing pain that radiates up the affected limb, according to Cleveland Clinic. Types Of Jellyfish To Look Out For According to Coffey, the U.S. is home to more than 9,000 species of jellyfish, and only about 100 are considered dangerous. —Meghan Overdeep, Southern Living, 11 July 2025

Making Their Lives Too Easy Wealth without work creates a dangerous illusion. —Anatoly Iofe, Forbes.com, 11 July 2025

While air temperatures on Friday were forecasted in the 70s, water temperatures in the region remained in the dangerous mid-50s range. —Anna Skinner, MSNBC Newsweek, 11 July 2025

For flash flood sirens, that means installing river gauges throughout the area so that water levels are monitored continuously and the sirens go off only when dangerous flooding is occurring, says Berginnis. —Rebecca Hersher, NPR, 11 July 2025

Word History

Etymology

see danger entry 1

First Known Use

15th century, in the meaning defined at sense 1

Phrases Containing dangerous

• armed and dangerous
• dangerous ground/territory
• dangerous waters
• on dangerous ground

Kids Definition

dangerous

adjective

dan·​ger·​ous ˈdānj-(ə-)rəs 

1

: exposing to or involving danger

a dangerous mission

2

: able or likely to cause injury

dangerous weapons

dangerously adverb

dangerousness noun

Legal Definition

dangerous

adjective

dan·​ger·​ous

1

: creating a risk of bodily injury

a dangerous condition of a public building

2

: able or likely to inflict especially serious bodily injury

a dangerous criminal with no regard for human life

a dangerous animal

also : deadly

3

: likely to engage in repeated criminal activity

a dangerous offender

Note: The activity that an offender is likely to engage in need not involve violence in order for the offender to be deemed dangerous.