municipal employee; city official
Refers to a person employed by a city government in an administrative or clerical role. The term is somewhat formal and may appear in official contexts.
He has worked as a municipal employee for many years.
I plan to take the employment exam for city officials.
市役所職員 is a more common and general term for city hall staff, whereas 市吏員 is a more formal or legalistic term.
Compound of 市 (city) and 吏員 (official, clerk). The exact historical derivation is uncertain, but the term is conventionally associated with municipal administrative personnel.