The name is derived from Simeon, son of Jacob and Leah, patriarch of the Tribe of Simeon. The text of Genesis (29:33) argues that the name of Simeon refers to Leah's belief that God had heard that she was hated by Jacob, in the sense of not being as favoured as Rachel.
"Because the LORD had heard that I was hated, he had therefore given me this son also: and she called his name Simeon."
implying a derivation from the Hebrew term shama on, meaning "he has heard"; this is a similar etymology as the Torah gives for the theophoric name Ishmael ("God has heard"; Genesis 16:11), on the basis of which it has been argued that the tribe of Simeon may originally have been an Ishmaelite group (Cheyne and Black, Encyclopaedia Biblica). In classical rabbinical sources, the name is sometimes interpreted as meaning "he who listens [to the words of God]" (Genesis Rabbah 61:4), and at other times thought to derive from sham 'in, meaning "there is sin", which is argued to be a prophetic reference to Zimri's sexual miscegenation with a Midianite woman, a type of relationship which rabbinical sources regard as sinful (Jewish Encyclopedia).