research bureau; research service; research council
Used as a suffix attached to organization names, such as government agencies or institutional bodies, to indicate a research or investigative division.
The Cabinet Research Bureau is in charge of policy research.
This report was compiled by the National Research Service.
調査部 is a research department within a company or organization, whereas 調査局 often implies a larger, more official bureau or agency.
Compound of 調査 (research, investigation) and 局 (bureau, office). The exact historical derivation is uncertain, but the combination follows standard Sino-Japanese word formation patterns.