After a short, two-day reprieve that saw the Dow Jones Industrial Average (DJINDICES:^DJI) gain nearly 200 points, the bears returned in full force on Thursday: nearly eight in 10 names lost ground in the stock market today. Leading the way, once again, were technology and biotechnology stocks, a fact that sent the Nasdaq Composite reeling, logging its worst intraday decline since 2011. The Dow, for its part, cratered 266 points, or 1.6%, to end at 16,170. 

Walt Disney (NYSE:DIS) shed 3.7% today, nearly finishing as the single worst performer in the Dow. As colleague Dan Caplinger noted earlier today, one of the advantages the Dow has over Nasdaq is its stability -- the 30 blue chip components are all titans of American industry. But while Disney and all its billions theoretically provide investors insulation from excessive volatility, even great companies can become risky stocks if investors become hyper-optimistic. I love Disney's enviable portfolio of multibillion-dollar franchises, but Wall Street may have this one priced to perfection at current levels.

Zulily's (NASDAQ: ZU) value is even more difficult to ascertain, since future cash flows of the flash-sale website are far more uncertain than Disney's. Uncertainty wasn't popular in the stock market today, and the stock plunged 7% as investors shed high-risk names today. Founded just five years ago, Zulily went public in November, and its stock has been all over the map since then. While Zulily should be applauded for growing sales from $18 million in 2010 to nearly $700 million last year, there aren't many barriers to entry in its industry, and Zulily's wild success is sure to attract a lot of competition. 

Rite Aid store in Oregon. Source: Wikimedia Commons

Finally, Rite Aid (NYSE:RAD) continued its fairytale run on Thursday, ignoring the tech and biotech meltdown to finish with 8.4% gains. The drug store reported its fiscal fourth-quarter results this morning, beating analyst expectations for both earnings and revenue. Not only did Rite Aid crush it last quarter; the company projected sales of $26 billion to $26.5 billion in the current fiscal year, easily topping the $25.8 billion Wall Street was looking for. If Rite Aid keeps the solemn vow it made in a press release this morning to offer "Eggstra-Special Treats This Easter," then April sales should be spectacular.