defiance – open resistance to an authority or opposing force
(Pronounced duh-fai-uhns)
To remember the definition of the word defiance, use the following mnemonic:
The fighting ants (defiance) showed open resistance to an opposing force.

Examples of defiance in a sentence
Their child's constant defiance was a constant source of frustration.
The new leader was met with defiance.
His defiance of the dictator sparked a nationwide resistance.