鸥 (ōu) — gull (bird), often used in compounds like 海鸥

鸥 (ōu) is a bound form meaning 'gull' — almost always seen in the compound 海鸥 (seagull). It rarely stands alone in modern Chinese.

Most characters — around four in five — are built this way: one part hints at the meaning, the other at the pronunciation.

This origin belongs to the traditional form 鷗; 鸥 is its simplified writing.

The traditional form 鷗 pairs 鳥 (bird) with 區 for the sound; the simplified 鸥 is a shorthand, and its right side is not the historical component.