Definition of "mad" in English

adjective

1. (chiefly British Isles) Insane; crazy, mentally deranged.

   • You want to spend a thousand pounds on a pair of shoes? Are you mad?
   • He's got this mad idea that he's irresistible to women.

2. (chiefly US; informal in UK and Ireland) Angry, annoyed.

   • Are you mad at me?

3. (chiefly in the negative, informal) Used litotically to indicate satisfaction or approval.

   • Wow, you really made this pie from scratch? I'm not mad at it.

4. (UK, Ireland, informal) Bizarre; incredible.

   • It's mad that I got that job back a day after being fired.

5. Wildly confused or excited.

   • to be mad with terror, lust, or hatred

6. Extremely foolish or unwise; irrational; imprudent.

7. (colloquial, usually with for or about) Extremely enthusiastic about; crazy about; infatuated with; overcome with desire for.

   • Aren't you just mad for that red dress?

8. (of animals) Abnormally ferocious or furious; or, rabid, affected with rabies.

   • a mad dog

9. (slang, chiefly New York, African-American Vernacular) Intensifier, signifying abundance or high quality of a thing; very, much or many.

   • I gotta give you mad props for scoring us those tickets. Their lead guitarist has mad skills. There are always mad girls at those parties.

10. (of a compass needle) Having impaired polarity.

adverb

1. (slang, chiefly New York, African-American Vernacular, UK and Ireland, dialectal) Intensifier; to a large degree; extremely; exceedingly; very; unbelievably.

   • He was driving mad slow.
   • It's mad hot today.
   • He seems mad keen on her.

verb

1. (obsolete, intransitive) To be or become mad.

2. (now colloquial US, Jamaica) To madden, to anger, to frustrate.