As a Noun: 1. The characteristic of being always determined to do what you want to do and to be very unwilling to change your mind. English = stubbornness, obstinacy. Informal English = pig-headedness. 2. A stubborn person. As a Verb or Adjective: 1. To be determined to do what you want to do and to be very unwilling to change your mind. English = (be) stubborn, (be) obstinate, (be) headstrong, (be) steadfast. Informal English = (be) pig-headed.