"Isaiah thanked me, which I didn't understand," the 28-year-old actress tells Entertainment Weekly. "He was almost grateful. I don't know Isaiah well, but he takes his work seriously and he loves his character."
Washington came under fire for using the epithet at the Golden Globe Awards in January while denying he'd used it previously against fellow "Grey's" star T.R. Knight. Heigl, who plays outspoken Dr. Izzie Stevens on the hit ABC medical drama, says she was "furious and frustrated" at the time, so she leapt to Knight's defense.
"He made a big mistake, and it was thoughtless and boneheaded, and I think he's very sorry and embarrassed," she says in the magazine's Friday issue. "This is something that will have changed the scope of his life."
Heigl, who stars in the new Judd Apatow-directed comedy "Knocked Up," speaks out in the interview, too, about her protracted contract negotiations with ABC. The bottom line, she says, is that she wants "the same respect they're showing the other actors."
And she says she doesn't like the label that seems to go along with a woman who stands up for what she wants.
"In this town, women who don't just snap and say, 'Okay, yessir, yes ma'am,' start to get a reputation for being difficult," she says. "But within the last five years, I've decided it's not worth it to me to be pushed around so much."
Heigl, who calls "The Notebook" one of her "all-time favorite movies," says she'd rather laugh than get too serious when it comes to movie roles.
"I just want to play happy people," she says. "I'm a commercial kind of gal, and yeah, I would love to do a 'Monster,' but I don't have any grand aspirations to do my Academy Award-winning movie. I love Kate Winslet, but I know I couldn't have her career."