This is the 817th most frequent Chinese word.
專業
"專業" means "professional" or "specialized field."
In this sentence, "專業" is used as an adjective to describe someone's expertise in their occupation.
他是一位專業的醫生。
He is a professional doctor.
Here, "專業" means 'major' or 'field of study,' referring to a specific area of expertise within academic or vocational training.
他的專業是電腦科學。
His major is computer science.
In this instance, "專業" functions as an adverb to describe the manner in which an action was conducted, implying skill and competence.