-or — one who, a person or thing that does (affix)

doctor A1

/ˈdɑktɚ/ A person who is trained and qualified to treat sick or injured people. M S

actor A1

/ˈæk.tɚ/ a person who performs in plays, films, or television M S

editor A2

/ˈɛd.ɪ.təɹ/ A person who corrects and improves writing before it is published. M S

sailor B1

/ˈseɪ.lɚ/ A person who works on a ship or sails boats. M S

conductor B2

/kənˈdʌktɚ/ The person who leads an orchestra or other musical group. M S

inventor B2

/ɪnˈvɛntɚ/ A person who creates or designs something new. M S