◐

See also: ◑ [U+25D1 CIRCLE WITH RIGHT HALF BLACK]

◐ U+25D0, ◐ CIRCLE WITH LEFT HALF BLACK ← ● [U+25CF] Geometric Shapes ◑ → [U+25D1]

Translingual

Symbol

◐

1. Contrast (on a television or monitor).
2. The last quarter (moon phase).

Japanese

Symbol

◐(せんしょう) • (senshō) 

1. 先勝, the first day of the 六曜 (rokuyō) calendar. Good luck before noon, bad luck after.