⿱

⿱ U+2FF1, ⿱ IDEOGRAPHIC DESCRIPTION CHARACTER ABOVE TO BELOW ← ⿰ [U+2FF0] Ideographic Description Characters ⿲ → [U+2FF2]

This symbol ⿱ became part of Unicode due to its inclusion at 0xA98B of GBK.

⿱

1. Indicates that two CJK ideographs are to be arranged together vertically to form a new ideograph.

   ⿱覀女 = 要

• Chapter 12.2 of the Unicode spec here (PDF)