複

Glyph origin
– lined garment.

Etymology
Cognate with. See there for more.

is an aspiration causative/iterative form of, hence literally "to make something double over".

Definitions

 * 1)  lined garment
 * 2) to repeat; to double; to overlap
 * 3) duplicate; double; overlapping
 * 4) complex
 * 5) again

Prefix

 * 1) diplo-, double

Etymology 1
From.

Etymology 2
From.