
der Arbeitskollege
coworker
A person you work with, usually in the same company or department.
Ich gehe in der Mittagspause oft mit meinen Arbeitskollegen essen.
I often go out to eat with my coworkers during my lunch break.
coworker
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coworker
A person you work with, usually in the same company or department.
Ich gehe in der Mittagspause oft mit meinen Arbeitskollegen essen.
I often go out to eat with my coworkers during my lunch break.
This word is a clear example of a German compound. It is made up of 'die Arbeit' (work), the linking '-s-', and 'der Kollege' (colleague). So it literally means a 'colleague from work.'
Mein Arbeitskollege hat mir bei dem Projekt sehr geholfen.
My coworker helped me a lot with the project.
The base word is 'Kollege' (colleague). The first part 'Arbeits-' specifies what kind of colleague it is. In the same way, you can describe other colleagues, for example 'Studienkollegen' (fellow students) at university.
Ich treffe mich heute Abend mit ein paar ehemaligen Arbeitskollegen.
I'm meeting a few former coworkers this evening.
Common verbs used with 'Arbeitskollege' (coworker) are 'sich gut verstehen mit' (to get along well with), 'zusammenarbeiten mit' (to work together with), or 'sich treffen mit' (to meet up with). The plural form 'Arbeitskollegen' (coworkers) is often used.
Sie versteht sich gut mit ihren neuen Arbeitskollegen.
She gets along well with her new coworkers.
employee
Mitarbeiter refers to an employed person from the perspective of a company or manager and does not imply direct collaboration. An Arbeitskollege, by contrast, is someone you work with, usually in the same company or department. Mitarbeiter is appropriate for the organizational role; Arbeitskollege is appropriate for the personal working relationship.

Mein neuer Arbeitskollege sitzt seit Montag neben mir.
My new coworker has been sitting next to me since Monday.
Die Abteilungsleiterin stellte den neuen Mitarbeiter dem Team vor.
The department head introduced the new employee to the team.