U.S. stocks retained sizable losses on Thursday, but recouped more than half of a steep dive, as investors dialed back concern that came with indications of trouble at one of Portugal's top banks.
"We'll have to get bigger, worse news than we've been getting to have a sustained decline," said Kim Forrest, senior equity analyst at Fort Pitt Capital.
The market's comeback from hefty losses could be as simple as people suffering from "non-participant remorse" opting to step in when they see a buying opportunity, said Forrest, who added: "anytime they see a dip like this, they'll go in; I think that's true of institutional investors too, and that makes these dips short-lived."
The market's initial unraveling came after Espirito Santo Financial Group, the biggest stakeholder in Portugal's Banco Espirito Santo, suspended trading in its shares and bonds, citing "material difficulties" at parent ESI.
Read MoreHere's what's happening in Portugal
"Not knowing something is a catchphrase for contagion and added volatility, and we've seen both of those injected into U.S. markets in no uncertain terms," said Andrew Wilkinson, chief market analyst at Interactive Brokers.
The Chicago Board Options Exchange Volatility Index, a measure of investor uncertainty, gained a point, or 8.4 percent, to 12.63.
That said, "fears were perhaps overblown" and Wall Street's initial reaction seems "excessive, given the size of Portugal and the potential for" reigniting a financial-system crisis in the euro zone, given there's little reason to believe that European authorities would not deal with the potential collapse of one of Portugal's largest banks in a prompt and orderly manner, Wilkinson added.
Peter Boockvar, chief market analyst at the Lindsey Group, had a bleaker take, saying the country-specific news from Europe "is a reminder that the region is barely growing, and their economy is as big as ours."
Coming back from an 180-point deficit, the Dow Jones Industrial Average fell 70.54 points, or 0.4 percent, to 16,915.07, with Home Depot falling hardest among its 30 components, 22 of which ended in the red.
Home Depot fell along with other home-improvement retailers after Lumber Liquidators Holdings cut its earnings outlook for the year.
Energy led sector declines and telecommunications paced gains on the , which dropped 8.15 points, or 0.4 percent, to 1,964.68.
"Part of me is very concerned because stores in middle America -- Tractor Supply and Wal-Mart -- their commentary on the missing shopper has gotten my attention," said Forrest, who also listed Family Dollar Stores and the Container Store as offering less-than-positive takes on the consumer in recent days.
"Adding up the commentary from retailers added up to today's downward slide," she said.
The Nasdaq.declined 22.83 points, or 0.5 percent, to 4,396.20.
For every share rising, more than two fell on the New York Stock Exchange, where 654 million shares traded. Composite volume neared 3.2 billion.
Investors sought safety in U.S. Treasuries and gold, with the yield on the benchmark 10-year note off 2 basis points at 2.536 percent and gold futures jumping $14.90, or 1.1 percent, to $1,339.20 an ounce on the New York Mercantile Exchange.
On Friday morning, Wells Fargo kicks off second-quarter earnings reports from the banking sector.
"We get the banks first, and it'll be interesting to see the net loans out; it looks like people borrow for cars and student loans, and that's about it," said Forrest, who questioned the extent that consumers are taking out loans for other reasons.
Ahead of Thursday's open, Wall Street bypassed another upbeat indicator on the U.S. jobs market, with stock-index futures only furthering their fall after applications for jobless benefits last week fell by 11,000 to a better-than-expected 304,000.
"We know the labor market has improved, that is not the issue. The market is facing what is going on in Europe and a Fed that is just a few meetings away from ending QE3," said Boockvar of expectations that the central bank's latest round of quantitative easing would end in October.
"Portugal's bank still has a problem, no matter what jobless claims were," said JJ Kinahan, chief strategist at TD Ameritrade.
Stocks slightly reduced their losses after data had wholesale inventories climbing 0.5 percent in May, pointing to a rebound in second-quarter GDP.
However, Boockvar said the report had nothing to do with the market coming off session lows.
"It's never a market-moving number; the first half hour of trading has its own dynamic, and then things settle out and we get to see what happens," Boockvar said.
On Wednesday, U.S. stocks climbed, recouping a chuck of the prior two-day drop, after minutes from the Federal Reserve's last meeting noted an improving economy and labor market, while setting the stage for the central bank's eventual exit from its course of monetary easing.
"This might please the Fed that people are more reactive to risk," said Forrest, referring to Thursday's trading action and concerns expressed by Fed officials of overly complacent markets.
"They pushed us to risky assets," she added.
—By CNBC's Kate Gibson
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