◑

See also: ◐ [U+25D0 CIRCLE WITH LEFT HALF BLACK]

◑ U+25D1, ◑ CIRCLE WITH RIGHT HALF BLACK ← ◐ [U+25D0] Geometric Shapes ◒ → [U+25D2]

Translingual

Symbol

◑

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

Japanese

Symbol

◑(せんぶ) • (senbu) 

1. 先負, the third day of the 六曜 (rokuyō) calendar. Bad luck before noon, good luck after.