Just as Frank Zappa proved himself the classic hippie prankster by naming his children Moon Unit and Dweezil in the 1960's, the actress Shannyn Sossamon, 26, established herself as a proud product of her times by naming her son, born in 2003, Audio Science.

"A name is free, it is something that everyone has, so if you are a celebrity, you are going to have to work that much harder to set yourself apart as a person with a specialized knowledge or a rarefied taste," said Pamela Redmond Satran, who has written baby-name books with Linda Rosenkrantz, including "Beyond Jennifer and Jason" (St. Martin's). She said a competitive impulse among stars seems to account for the recent bonanza of unlikely baby names.

"In a weird way, it's like anorexia" in Hollywood, Ms. Satran said. "Anyone can be thin. The famous have to be thinner."

They also have a traditional role as tastemakers. It's hardly a coincidence that the name Ryder, which was the 901st most popular boy's name in the country in 2001, according to Social Security Administration statistics, jumped to 341 in 2004, the year Kate Hudson and Chris Robinson chose it for their newborn son.

But as regular people ¡ª the sort who wait in line at restaurants and pay for their own clothing ¡ª try to catch up, the stars are pushed further into the realms of obscure names, in an effort to stay ahead of this particular fashion curve. So stars troll deeper into the Old Testament for name ideas (both Bono and Wynonna Judd have an Elijah, and Cynthia Nixon has a Charles Ezekiel), into world geography (David and Victoria Beckham have a Brooklyn, and Summer Phoenix and Casey Affleck have an Indiana) or even into Grandmother's attic. (Jude Law dusted off the name Iris for his daughter, and Heath Ledger and Michelle Williams exhumed the name Matilda for their first child last fall.)

Some therapists said the celebrity impulse to foist odd names on their children amounts to simple narcissism by the parents, and the resulting status comes at the child's expense. The children, after all, are the ones who will have to raise their hands every time a teacher calls out "Coco" or "Eulala."

"It's like having a mini me," said Robert R. Butterworth, a clinical psychologist in Los Angeles, who has had actors on his patient roster. "The child is a part of them, not an individual. It's an appendage."

The burden of celebrity falls even on the unborn. The child Brad Pitt and Angelina Jolie are expecting has already been a cover subject for magazines.

Other psychologists, however, believe fears for the child's well-being are overblown. If, for example, Harvey Keitel's son, born in 2004, feels a bit conspicuous being named Roman, he will at least have company. Both Cate Blanchett and Debra Messing named sons Roman that year.

Besides, the offspring of the Hollywood elite have other matters to discuss in therapy, said Dr. Berman, who said she has counseled several: "With kids of celebrities, in all honesty, the other issues are so big this one pales in comparison."