Billie Eilish wore a partially sheer dress she said looks like something from Mrs. Claus' closet while hosting 'Saturday Night Live'

• Billie Eilish, 19, hosted and performed last night on "Saturday Night Live."
• Eilish poked fun at her outfit during the opening monologue.

Billie Eilish wore a partially-sheer dress that looked like it was plucked straight from Mrs. Claus' closet during her "Saturday Night Live" appearance.

Eilish became the latest celebrity to host and perform on "Saturday Night Live" during this week's episode. The 19-year-old, who is a nominee at the 2022 Grammy Awards, wasn't afraid to talk about her sense of style during her opening monologue.

Eilish wore a partially-sheer dress adorned with lace, tulle, and broderie anglaise that Simone Rocha designed for her spring 2022 ready-to-wear collection, according to Vogue. The dress — paired with knee-high boots — included red accents near the waist and various fabric textures layered atop one another in an eye-catching display.

"I wanted there to be a lot of texture, because it's an in-person show, and everyone will be quite close to the garments for the first time," Rocha told Vogue's Sarah Mower after the collection's debut in September 2021.

During "Saturday Night Live," Eilish described the dress as an outfit Mrs. Claus would wear on a night out.

"If you don't know me for my music, you may know me for my hair or my clothes," she said. "That is why I decided to dress like Mrs. Claus going to the club, but actually, I'm only wearing this because after the show I got to go get married in an anime."

She then spoke about her past fashion choices, specifically her decision to wear baggy clothes in public and at red carpet events.

"Some people wonder why I started wearing baggy clothes and there was actually a good reason," Eilish said.

She continued, "It wasn't just for comfort or for style. This is hard to say for me, but the real reason I wore big, oversized clothes back then is … I was actually two kids stacked on top of each other trying to sneak into an R-rated movie."

A representative for Billie Eilish did not immediately respond to Insider's request for comment.

On Saturday's episode, Eilish performed her songs "Happier Than Ever" and "Male Fantasy." She also acted in a number of skits, including "Hip-Hop Nativity" with Bowen Yang and other castmates.

Eilish has been outspoken about body positivity and overcoming her insecurities. In an April 2020 interview with Dazed, Eilish said she previously wore oversized clothes because she hated her body.

"The only reason I did it was 'cos I hated my body," Eilish said.

During the interview, she also recalled when a photo of her wearing a white tank top hit the internet in June 2019 and prompted comments from fans. Eilish told the outlet she remembered some of the hurtful comments, including,"'I don't like her any more because as soon as she turns 18 she's a whore.'"

"Like, dude. I can't win. I can-not win," she told the outlet.