Literal translation:
* Matigas ang ulo (literally "stubborn head") - This is a common phrase used to describe someone who is defiant or stubborn.
* Matapang (brave, courageous) - Can be used to describe someone who is defiant in a positive light.
Other options depending on the context:
* Nagmamatigas (resisting, refusing)
* Sumasalungat (opposing, challenging)
* Hindi sumusunod (not obeying)
* Walang pakundangan (reckless, without regard)
Example sentences:
* "Matigas ang ulo niya kaya hindi niya ako sinunod." (He's stubborn so he didn't listen to me.)
* "Nagmamatigas siya sa mga kahilingan ko." (He is resisting my demands.)
* "Sumasalungat siya sa mga patakaran." (He is challenging the rules.)
* "Hindi sumusunod ang mga bata sa kanilang magulang." (The children are not obeying their parents.)
* "Walang pakundangan niyang sinabi ang mga salitang iyon." (He said those words recklessly.)
The best translation will depend on the specific situation you are describing.