The word main is used to describe something or someone as the most important. Mainly is an adverb used to talk about the central thing or person in a situation.
My main job is to wash the dishes at the restaurant. I hope to work my way into a position as a waitress.
My days mainly consist of going to work and coming home to cook dinner for my family. There is not much time for leisure activities.
A large expanse or area of something can be referred to as main. Main can also be used when talking about something done with sheer force, such as in the phrase by main force.
When we saw the accident, we stopped and tried to help. We were able to pull the driver out of the car by main force.
The captain was expecting a smooth trip when the ship left the inlet. However, it soon got into the main sea and couldn't return to port again.
Chief is a word used to describe something or someone as the main, or principal, item or person. It means that you or it is the most important part. The word chiefly can be used as an adverb to describe something as principal.
Your chief responsibility will be the laundry. Everyone is being assigned a task that they will accomplish for the group.
The word chief can also be an informal name used to refer to the person in charge of something. The idioms editor in chief and commander in chief also refer to the person in charge. It can also be used with a name to create a formal title.
I am the commander in chief of this operation. The university newspaper would not be published if I did not organize the reporters and get their stories to print.
Chief Tutikah was responsible for the quality of life in his tribe. Any important decisions about lifestyle went through him.