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adjective dan·ger·ous \ˈdān-jə-rəs; ˈdān-jərs, -zhrəs\

Simple Definition of dangerous

  • : involving possible injury, harm, or death : characterized by danger

  • : able or likely to cause injury, pain, harm, etc.

Source: Merriam-Webster's Learner's Dictionary

Full Definition of dangerous

  1. 1 :  exposing to or involving danger <a dangerous job>

  2. 2 :  able or likely to inflict injury or harm <a dangerous man>

dangerously adverb
dangerousness noun

Examples of dangerous in a sentence

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

  2. He often drives at dangerous speeds.

  3. The city can be a dangerous place to live.

  4. The storms may cause dangerous flooding.

  5. He is wanted for assault with a dangerous weapon.

  6. the most dangerous of drugs

15th Century

First Known Use of dangerous

15th century

Synonym Discussion of 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>.

DANGEROUS Defined for Kids


adjective dan·ger·ous \ˈdān-jə-rəs, ˈdānj-rəs\

Definition of dangerous for Students

  1. 1 :  involving possible harm or death :  full of danger <dangerous work>

  2. 2 :  able or likely to injure <A chain saw is a dangerous tool.>

dangerously adverb

Law Dictionary


adjective dan·ger·ous

Legal Definition of dangerous

  1. 1 :  creating a risk of bodily injury <a dangerous condition of a public building>

  2. 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. 3 :  likely to engage in repeated criminal activity <a dangerous offender>

Additional Notes on dangerous

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

Seen and Heard

What made you want to look up dangerous? Please tell us where you read or heard it (including the quote, if possible).


a timid, meek, or unassertive person

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