ゲン, ガン, もと, ちか, はじめ, はる, ゆき, よし
beginning, former time, origin
JLPT4 G2 S4 F192
As per 兀# (head) + a horizontal line → *head* → *origin*; *cause*; *raw material*; *capital*; *prime element* (← head as source and beginning; compare 頭) → *former* (← prior ← original). 元 was devised to replace 兀 after the latter lost its original connection with the head.
[Full Kanji Etymology List]