Someone or something that does what they want, or something done on purpose. 
A person does not act willfully if the person acts as a result of a good faith misunderstanding of the requirements of the law. Intent and motive should not be confused. Motive is what prompts a person to act, while intent refers to the state of mind with which the act is done. There is no precise definition of the term willful because its meaning largely depends on the context in which it appears. It generally signifies a sense of the intentional as opposed to the inadvertent, the deliberate as opposed to the unplanned, and the voluntary as opposed to the compelled. Willful Blindness Law & Legal Definition. Willful blindness is a term used in criminal law to refer to the acts of a person who intentionally fails to be informed about matters that would make the person criminally liable. Intentional; not accidental; voluntary; designed. There is no precise definition of the term willful because its meaning largely depends on the context in which it appears. It generally signifies a sense of the intentional as opposed to the inadvertent, the deliberate as opposed to the unplanned, and the voluntary as opposed to the compelled. adjective. The definition of willful is someone or something that does what they want, or something done on purpose. 1  An example of someone willful is a child that refuses to eat at a meal. 2  An example of something willful is the action of a puppy that is determined to eat all of the shoes it can find. The definition of willful is someone or something that does what they want, or something done on purpose. 1  An example of someone willful is a child that refuses to eat at a meal.
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define willfully