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 of dangerous

• 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

Remember when Mizzou had one of the most dangerous offenses in the country, and Ahmad Hardy seemed like a legit candidate for the Heisman Trophy? —Quentin Corpuel, Kansas City Star, 16 Nov. 2025

Sac State leads the Big Sky in rushing and is third in the FCS in rushing yards and yards per game, and the Hornets kept with their norm against a Vandals team that came in as a dangerous 4-6 team. —Joe Davidson, Sacbee.com, 16 Nov. 2025

Bleach can also have a dangerous reaction with cleaners that contain ammonia, hydrogen peroxide, or acids like vinegar. —Brandee Gruener, Southern Living, 16 Nov. 2025

This tragedy underscores the extreme dangers of attempting to cross the maritime border in unsafe, overloaded vessels and during dangerous weather conditions. —Mandy Taheri, MSNBC Newsweek, 16 Nov. 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.