The phrase "peachy undertones" refers to having a hint of peach color or shades in something, usually when talking about makeup, complexion, or a particular hue. Full definition
This wild summer shade looks even more provocative and lush in the fall, thanks to refined peachy undertones and intensely creamy textures. (allure.com)
It all depends on your skin tone, for us Indians either a brown or peachy undertone nude shade looks the best. (notonlymakeup.net)
It is such a beautiful highlighter with pretty peachy undertones. (elisabethhayes.com)