adj. cra·zi·er, cra·zi·est
a. Mentally deranged.
b. Informal Odd or eccentric in behavior.
2. Informal Departing from proportion or moderation, especially:
a. Possessed by enthusiasm or excitement: The crowd at the game went crazy.
b. Immoderately fond; infatuated: was crazy about boys.
c. Intensely involved or preoccupied: is crazy about cars and racing.
d. Foolish or impractical; senseless: a crazy scheme for making quick money.
e. Intensely annoyed or irritated: It makes me crazy when you don't tell me you're going to be late.
3. Disorderly or askew: One of the old window shutters hung at a crazy angle.
Informal Extremely; very: That restaurant's always crazy busy on weekends, but it's worth the wait.
n. pl. cra·ziesIdiom:
One who is or appears to be mentally deranged: "To them she is not a brusque crazy, but 'appropriately passionate'" (Mary McGrory).
like crazy Informal
To an exceeding degree: They were running around like crazy.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.