downstairs neighbor
Refers to a person living on the floor directly below in an apartment building or multi-story dwelling.
The downstairs neighbor is making noise late into the night.
Used in workplace or organizational contexts to refer to someone of lower rank or position.
He is good at delegating work to his subordinates.
Standard kanji spelling for both senses.
Kana spelling used when the kanji 下 might be ambiguous or for emphasis.
Compound of 下 (した, 'below') + の (possessive particle) + 人 (ひと, 'person'). Literally 'person of below'.