Where the shape comes from
A large eye turned on its side, drawn as a subject would hold it: lowered, not meeting the ruler’s gaze directly. It names the court official outright in 大臣, a minister, and lies down beside 人, a person, in 卧, to lie down, to recline, the same lowered eye of someone now resting rather than merely bowing.
汉字 filed under 臣
No published character on HSK Guide is filed under this radical yet. 汉字库.