This is the 16778th most frequent Russian word.
служебные
"служебные" means "service" or "official" (relating to work or duty).
The word "служебные" here refers to documents associated with official or professional use.
Эти служебные документы нужно подписать.
These official documents need to be signed.
In this case, "служебный" describes a designated entrance primarily used for work-related purposes.
В здании есть служебный вход для работников.
The building has a service entrance for staff.
Here, "служебные" pertains to words that perform grammatical functions rather than carry independent meanings.