经理(jīng lǐ) - manager in Mandarin

经理 (jīnglǐ) is the manager of a business unit: a shop, a department, a restaurant, a branch. It is a job title with a rung on the ladder, which is why it takes modifiers so readily. 总经理 is the general manager or managing director, 副经理 is the deputy, and 销售经理 is the sales manager.

The habit worth copying is using it as a form of address after the surname. 王经理 is the normal way to speak to or about Manager Wang, exactly as 李老师 works for a teacher. English has almost nothing like this, and skipping it in a Chinese office sounds oddly flat.

The trap is confusing it with 老板 (lǎobǎn). 老板 is the boss or owner, the person whose money is at risk; 经理 is an employee with authority delegated to them. A small shopkeeper is a 老板 and never a 经理. Calling the owner of a family restaurant 经理 quietly demotes them.