Delete “bear market” from the vocabulary of the stock trade. The lightning speed at which share prices move has rendered it obsolete.

No one ever really knew what a bear market was anyway. There was no universally accepted definition of the term. Had there been, the New York Stock Exchange could have invented a circuit breaker to combat it.

The notion, though, was always one of two dimensions, magnitude and time.

Depending on the definer, the Dow Jones Industrial Average or the Standard & Poor’s 500 Index or maybe both had to fall anywhere from 10 percent to 20 percent.

The time during which this happened wasn’t stated even that precisely. The assumption was that it lasted long enough for investors to think their fingertips were being sanded off.

Today, pundits still refer to market slumps of 10 percent or more as bear markets. But declines of that size now occur in days rather than months or years. The bad news comes so fast that investors think their fingertips are being chopped off.

If you’ll excuse a painful reminder, the S & P; 500 sank 11.2 percent in just 15 trading days in March and April. The Nasdaq Composite Index an electronic market undreamed of when the first analyst declared a bear market plummeted 34 percent in only 25 days during the same two months. In one day, April 14, the Nasdaq fell 10 percent if you’ll allow rounding off 9.7 percent.

There are two possible explanations for this suddenness. 1) Events speed up to the pace of the computers that control us. 2) Society now demands immediate gratification but sometimes gets instant mortification.

Whatever the reason, the term no longer applies.

“The old-fashioned bear market certainly is dead,” says Yale Hirsch, president of Hirsch Organization, a publisher of market information in Old Tappan, N.J.

There actually hasn’t been a long, grinding bear market for a quarter-century. In the seven years ended with 1975, the S & P; 500 fell 13 percent, though many analysts wouldn’t say the bear market lasted that long.

Hirsch says this period was marked by two bear markets the 13-month decline of 1969-70 caused primarily by the Vietnam War and the 21-month slump of 1973-74 triggered by soaring oil prices and interspersed with months of rising prices, or bull markets. Over the years, the average bear market lasted 10 months, Hirsch says.

The good thing about warp-speed market declines is that stocks seem to recover almost as fast. After its big one-day drop in April, the Nasdaq index jumped 12.4 percent over the next two trading days. Your fingers were still whole.

For all the Internet-era volatility, the path of the stock market hasn’t changed all that much. Over time, share prices rise. This doesn’t mean you can’t lose money but for the patient, the bull market prevails, though with violent interruptions.

The bear market should wander off into the land of myth, but old ideas have a way of lingering. Hirsch says he just keeps changing his definition of a bear market to suit the times. His current one: “You go to the scene and count the bodies.” It can happen in a heartbeat.

David Pauly is a columnist for Bloomberg News.