Looking at Pete Hamill, with his pretty, round Irish face, his engaging manner, his hard-won reputation as a newspaper columnist, you can't help thinking - It must be awfully hard to be a man these days.

For Pete Hamill is stuck with what women have been complaining about for years: he's being defined by the dates he's seen with. And the women he's seen with - Shirley MacLaine, Jackie Onassis - are the ones who make the news, who are the shining repositories of gossip and publicity, the staples of the National Enquirer and the National Star.

And they are saying - oh God, they're just saying everything you can think of. A romantic triangle - Jackie winning, Shirley devastated, Jackie and Pete collaborating on a book. All lies and untruths, as you can imagine . . .

"I mean the National Star reported that I'd said that Jackie's the most wonderful girl I'd ever met. And that same piece had me going to Newport to meet her mother - I've never MET her mother. Or that I go to Elaine's with Jackie. I've NEVER been to Elaine's with Jackie.

"Well, you don't mind that in the National Star. But in the so-called [WORD ILLEGIBLE] press . . ."

Pete Hamill, Brooklyn-born, self-taught high school drop-out and really, [WORD ILLEGIBLE] you think about it, at 42, the [WORD ILLEGIBLE] of the old-time reporters [WORD ILLEGIBLE] mixed with absolutely everyone high life and low life, and never felt the burning desire to acquire a Masters degree from the Columbia University School of Journalism - Pete Hamill is asked how he would have responded if 10 years ago, someone had told him he'd be dating Jackie one day.

"I don't know what I would have said 10 years ago," says Hamill.

But - alas - somebody said it for him. Press tycoon Rupert Murdoch, an Australian spoiler and new owner of the New York Post and almost every other written word in New York City, was evidently a mite miffed with Pete Hamill lately. Hamill had written a column for the Daily News, attacking the New York Post's coverage of the Alice Crimmins affair.

Well, Murdoch knew how to deal with that. He dug up an old column Pete Hamill had written on Jackie back in the old days when Hamill was still working for the New York Post, and Jackie was still married to Ari.

"That column never ran," says Hamill, who pulled it at the last minute because he felt it was too strong. But the New York Post must have felt its time and come. And so for several days running it ran excerpts of a rather strident attack on Jackie's alleged $10-million marriage contract with Ari. Under the headline - WHO WROTE THIS?

Not willing to keep its readers in suspense for too long, the Post assuaged their curiosity by running a photo of Jackie and Pete Hamill on the last day.

"It's typical (of Murdoch)," Hamill says glumly. "He went around trying to wreck me." Fortunately he had told Jackie O. what he had once written about her.

He sighs. "You get a lot of stories about a big triangle. That's a lot of b - s - . . . Shirley and I will be friends the rest of our lives. She's my friend."

Well, Hamill is told, there wouldn't be any such stories - or at least no one would care - if he wasn't always seen with such famous ladies. Famous middle-aged ladies. For let us remember that in this Polanski era, it is not always usual for the middle-aged male to seek out his female contemporaries.

"Not middle-aged." He shakes his head, amused. "I like to call them 'grown up.' I don't like helping girls with their homework. I like grown-up ladies. There's a connotation to middle-aged - it's part of what we've done to women."

God, that felt good . . . Now you can see it all. You can see what makes him so appealing to the grown-up women he's seen with. Pete Hamill is clearly a woman-worshipper, a tender and irresistable quality in any man.

"I like women," he says simply. "I think women are more intelligent than men. But my life is much more involved with other things than women . . . The problem is if you're trying to write novels - if you say to yourself I'm only going to know a certain number of people - then you end up writing about the copy desk."

But this time around, anyway, Pete Hamill did not write about the copy desk. He wrote about incest - mother/my-son-the-boxer incest in "Flesh and Blood."

"It's spooky," he says. "You wonder what will people think of my mother who's a very gallant woman from Northern Ireland."

Well, never mind that. What did his mother think of the novel?

"I said, 'Mom - what do you think?' She said, 'Well'. I caught my breath once in a while.'" He grins fondly. "She landed in New York the same day the stock market crashed . . ."

And have seven children - Pete Hamill being the oldest. In his sophomore year of high school he had to drop out to go to work as a sheet metal worker in the Brooklyn Navy Yard.

Growing older isn't all bad. Pete Hamill got $100,000 from CBS, which is making his new book into a TV movie. He wrote most of the screenplay for "French Connection II." His closest friend is boxer Jose Torres. And even though he and Shirley MacLaine are no longer living together (that ended a year-and-a-half ago) they are still an item.

"It's never easy," he says of their break-up. "Particularly when a thing gets larded with cliches imposed generally from the outside."

They didn't break up for this reason, he says, but at one point he wanted to get married - and Shirley didn't. It seems to be Hamill's fate in life to be the model for role reversal.

"It's very hard to talk about that," he says, referring to his six years with Shirley MacLaine. "Not because there is nothing to say about it. But because I have too much to say about it.

"Because . . ." here he smiles gently, a bit sadly, "because life is so complicated."