Negative Equity. This happens when your house value is less than the purchase price minus your down payment.
Joe put 20% down on a $500,000 house, the market crashed and the house is only worth $380,000. Joe now has $20,000 of Nequity.
trading in a vehicle when the amount still owed is greater than the value of the vehicle. (negative equity)
The nequity (negative equity) in my car was $2200.00. I owed more than it was worth.