The Dow Jones industrial average plunged 1,175 points, or 4.6%, erasing its gains for the year.
The Dow's drop on Monday was its biggest in terms of points, but it had a larger percentage drop as recently in 2011.
The Dow is down 8.5% from the record high it hit in late January.
The slump began on Friday as investors worried that higher inflation and interest rates could derail the long-running rally.
At one point the Dow was down as much as 1,600 points.
The Dow ended at 24345.
The Standard & Poor's 500, the benchmark for many index funds, fell 113 points, or 4.1%, to 2648. The Nasdaq fell 273, or 3.8%, to 6967.
Bond prices rose. The yield on the 10-year Treasury fell to 2.73%.