These are classic signs of a bear market

The market is getting ugly.

Stocks accelerated their declines on Wednesday with the S&P 500 dropping more than 3 percent at one point and falling to its lowest level since February 2014. The large-cap index is now down more than 10 percent this year, with a shocking 88 percent of its components in a correction or worse. According to one technician who has a history of calling tops, investors should sell into any rally.

"A bull is defined by two things, a succession of peaks and troughs that are higher than the preceding ones … [and] a period of broad strength where most sectors are participating," Carter Worth told CNBC's "Fast Money" this week. "Both of which we don't have right now."

Instead, Worth characterizes the current climate as classic bear market behavior, and he drew a comparison to past instances where a break below trend led to dire losses.

He pointed to the bear market of 1973-74, where stocks fell more than 40 percent after breaking trend, as well as the tech bubble, which saw a more than 30 percent drop in the market, and most recently, the financial crisis, when the market tanked 50 percent from its high (see charts below).

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"How low we go [this time] is anybody's guess; I have my own price objectives for the market," added Cornerstone Macro's head of technical analysis. On "Fast Money" early this month, Worth, who has been calling for a bear market for some time, said he expected the S&P 500 to fall as low as 1,600, which is another 12 percent from its current price.

It's not the first time Worth has called a top. In 2007, he also appeared on CNBC and declared the end to the bull run.

Of course, Worth expects to see countertrend rallies, like Tuesday of this week when the market managed to stay in the green, but warned they "aren't important," and investors should not be chasing dips in order to participate in the small and rare rallies that will occur in the near future.

"Is this a time to be saying I have to find myself a time to buy?" he questioned. "No, it's a time for caution."