noun
lower branch; subordinate organization; substructure
Refers to a branch, division, or unit that is under a larger organization, such as a local chapter, subsidiary, or affiliated group.
この下部組織は全国に支部を持っている。
This subordinate organization has branches nationwide.
彼は党の下部組織で活動している。
He is active in the party's lower branch.
支部 is a more common word for a branch office or local chapter, while 下部組織 emphasizes the hierarchical relationship as a lower-level body within a larger structure.
傘下 means 'under the umbrella of' and is often used for subsidiaries or affiliated companies, but it is an attributive noun, not a standalone noun like 下部組織.
Compound of 下部 (かぶ, 'lower part') and 組織 (そしき, 'organization').