What constitutes a love connection for Jennifer Aniston, who recently dismissed rumors that she had a "secret date" with Keanu Reeves? Apparently some friendly chitchat over dinner. Star is convinced the actress has a "new man" in Sam Rockwell after they were spied breaking bread together at a New York eatery earlier this month.

"She seemed friendly and flirty," a spywitness-cum-body language expert recalls to the tab.

And even though their tête-à-tête wasn't exactly intimate -- several pals reportedly tagged along -- that hasn't stopped the tab from declaring them "a perfect match."

"Jen is in the process of trying to reinvent herself career-wise," alleges a source. "So Sam is perfect. He hangs with the New York theater and acting crowd that Jen would kill to be a part of."

But Rockwell, who co-stars with Jen's ex-hubby Brad Pitt in the upcoming (and bad-buzz-plagued) "The Assassination of Jesse James by the Coward Robert Ford," is quick to dismiss the hook-up whispers as so much hooey.

"There's nothing going on between us," he tells Star. "We might be doing a movie together -- that's the dish."

Aniston's rep seconds the romance rebuttal, telling us, "Jennifer is not romantically linked to Sam Rockwell."

In related rumor rejection news, reports that Leonardo DiCaprio, 32, is planning to make things legal with ultra-leggy (and previously married) Israeli model Bar Refaeli, 21, may be a bit premature.

Star, in a story headlined, "Sorry Girls ... Leo to Wed!" claims the comely couple, who have been dating for a year, held an engagement party on March 11 in Tel Aviv, where they had been visiting Refaeli's parents.

"Leo and Bar stood up to announce their engagement with a toast," a source shares with the mag. "Everyone started cheering, and then Bar said that Leo had asked her to marry him -- and that she had said yes!"

But a DiCaprio source assures Us Weekly that there's no truth to the nuptial chatter, scoffing, "It's complete BS. Not true. Made up by a supermarket tabloid."

As for Leo's "Meet the Refaelis" moment, the insider insists, "Just because you see the parents doesn't mean there is an engagement."

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