Where does “𒁀” come from?

𒁀 (Akkadian) comes from Sumerian 𒁀, from Akkadian 𒀀 — water; heir.

Ancestry of “𒁀”, step by step

Step	Language	Word	Meaning
1	Sumerian	𒁀	allotment, distribution, share
2	Akkadian	𒀀	water; heir