noun
superior; supervisor; head of one's department
Refers to the person in charge of the organizational unit one belongs to, such as a department head or section chief. Common in workplace and bureaucratic contexts.
申請書には所属長の印鑑が必要です。
The application form requires the seal of your department head.
所属長に相談してから決めます。
I'll decide after consulting my supervisor.
部長 is a specific title for a department manager, whereas 所属長 is a functional term for the head of whatever unit one is assigned to, which could be a section, department, or other group.
Compound of 所属 (shozoku, 'affiliation' or 'belonging to') and 長 (chō, 'head' or 'chief').