IPA: /ˌɛdɪˈtɔːrɪəlɪst/
KK: /ˈɛdɪtɔːrɪəlɪst/
A person who writes articles that express opinions or viewpoints, usually for a newspaper or magazine.
The editorialist shared her thoughts on the recent political changes in the country.
Editorialist → It is formed from "editor" (from Latin "editus", meaning to bring forth or publish) and "-ialist" (a suffix indicating a person who practices or is concerned with a particular field). An editorialist is a person who writes or expresses opinions in an editorial capacity, bringing forth ideas and opinions for public consideration.
Think of someone who 'brings forth' ('editor') their thoughts and opinions in writing, which is what an editorialist does.