孑

A pictographic character. The character is believed to depict a single arm or limb without its pair, symbolizing something incomplete or standing alone. From this image developed the meaning solitary or alone.
Semantic development: - a single or incomplete limb; - something standing alone; - solitary or lonely state.

혈혈단신 (孑孑單身) — completely alone; without family or support

This expression describes a person who is entirely alone without relatives or assistance.

In classical literature, 孑 often symbolizes loneliness or isolation. The character appears in the expression 孑孑, emphasizing the sense of being completely alone.
Related characters: 子 — child

孤 — orphan; lonely

單 — single; alone

獨 — alone