Butter yellow has been applied to a wide spread of items lately: cocktail dresses, jeans, jackets, hair clips, handbags and stand mixers. It has been slathered onto the walls of restaurants and home kitchens, and has oozed onto red carpets and the stages of major pop-music tours.

Like the dairy product the color is named for, butter yellow ranges in tone from golden to almost white. And it has captured the fascination — and wallets — of a growing number of people.

“It will be the fashion color for the spring season,” said Jodi Kahn, the vice president of luxury fashion at Neiman Marcus. This spring, the department store went all-in on butter yellow, offering it in the form of items like Alaïa sunglasses, Vince sneakers and basketball-style shorts by Dries Van Noten.

Ms. Khan said the color’s biggest selling point was its mood-lifting property. Butter yellow “has a bit of positivity and warmth,” she said, adding that it goes well with many neutral tones — white, navy, brown — that tend to populate wardrobes.

After being adopted by high-end labels like Jacquemus and Auralee, the color has gone on to infiltrate the offerings of brands across the pricing spectrum.