1. 1. To oppose or resist with boldness and assurance: defied the blockade by sailing straight through it.
   2. To refuse to submit to or cooperate with: defied the court order by leaving the country.
2. To be unaffected by; resist or withstand: "So the plague defied all medicines" (Daniel Defoe).
3. To challenge or dare (someone) to do something: She defied her accusers to prove their charges.

[Middle English defien, from Old French desfier, from Vulgar Latin *disfīdāre : Latin dis-, dis- + Latin fīdus, faithful.]

SYNONYMS   defy, brave, challenge, dare, face. These verbs mean to confront boldly and courageously: an innovator defying tradition; braving all criticism; challenged the opposition to produce proof; daring him to deny the statement; faced her accusers.

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.