This is the 3107th most frequent Russian word.
коллег
"Коллег" is the genitive plural and accusative plural form of "коллега," meaning "colleagues" in English.
The word "коллегами" denotes the instrumental plural form of "коллега" (colleague), referring to individuals from the speaker's workplace.
Я обедал с коллегами в кафе.
I had lunch with colleagues at the café.
The word "коллега" is singular and used in the nominative case, introducing a new coworker.
У нас на работе новый коллега.
We have a new colleague at work.
The word "коллеги" is the plural form in the nominative case, denoting multiple coworkers performing an action.