The Hebrew betsa (H1215) denotes gain made through violence, greed, or injustice — profit that comes at another's expense through dishonest means. It is consistently used in a negative sense associated with covetousness and oppression.
Betsa appears in Scripture's most powerful warnings against greed. Jethro advises selecting leaders who hate betsa (Exodus 18:21) as a qualification for justice. The prophets condemn Israel's leaders who exploit their positions for personal enrichment. The New Testament equivalent is pleonexia — both point to the same spiritual root: trusting wealth over God, which Jesus calls idolatry.