Latin word officium comes from Proto-Indo-European *h₃op-, and later Latin ops ((plural) resources, wealth. (singular) power to help.)

Detailed word origin of officium

Dictionary entry	Language	Definition
*h₃op-	Proto-Indo-European (ine-pro)
ops	Latin (lat)	(plural) resources, wealth. (singular) power to help.
officium	Latin (lat)	(figurative) an obligatory service, visit, or gesture. Duty, service. Office.