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

Yet, that is why the Knicks are so dangerous in these playoffs. —James L. Edwards Iii, New York Times, 28 May 2026

Virtually no research exists on the potential long-term effects on children, but the chemicals are undeniably dangerous. —Lisa Song, ProPublica, 27 May 2026

Authorities are warning residents not to throw lithium-ion batteries in the trash after one sparked a dangerous fire inside a Roseville garbage truck. —Madisen Keavy, CBS News, 27 May 2026

Gregory Raso has been charged with seven counts of assault and battery, seven counts of civil rights violation, and one count of assault and battery with a dangerous weapon. —Lance Reynolds, Boston Herald, 27 May 2026

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.