参

Top 厶 is the indexing radical - Kangxi #28, originally a curl picturing self-enclosure or private possession. Sits at the top of 参 as a stylized cap; in older forms this position drew a head, ginseng root, or a starry cluster, but the modern simplification reduces it to the abstract two-stroke 厶. Same radical: 去 to leave, 县 county.

Middle 大 is the outstretched-figure pictograph - arms wide, legs apart. In 参 it is the body of a standing person; below 厶 and above the trailing 彡 hair-strokes, the picture is a human figure adorned with streaming locks or stars. This is the ancient meaning of 参 as one of the 28 lunar mansions (Orion).

Bottom 彡 is the three-stroke flourish radical, picturing flowing hair, light-rays, or fine streaks. Below 大 it represents either the streaming hair of an adorned figure or the rays of starlight from the Shen (Orion) constellation. Same family: 形 shape, 影 shadow, 须 beard - all using 彡 for visual ornament.