The fish radical on the left, a pictograph of a fish. It supplies the meaning, marking the word as a species of fish, the same family as 鲨 and 鲸.
phonetic
䍃yáo
ancient vessel; phonetic
Fills the right side and carries the sound yáo. It is itself a rare graph for an old pitcher; the same phonetic appears in 摇 and 遥, here lending pronunciation only.